diff --git a/native/jni/com_android_inputmethod_latin_BinaryDictionary.cpp b/native/jni/com_android_inputmethod_latin_BinaryDictionary.cpp
index cb76c33..13a9b57 100644
--- a/native/jni/com_android_inputmethod_latin_BinaryDictionary.cpp
+++ b/native/jni/com_android_inputmethod_latin_BinaryDictionary.cpp
@@ -242,15 +242,15 @@
     env->GetFloatArrayRegion(inOutWeightOfLangModelVsSpatialModel, 0, 1 /* len */,
             &weightOfLangModelVsSpatialModel);
     SuggestionResults suggestionResults(MAX_RESULTS);
-    const PrevWordsInfo prevWordsInfo = JniDataUtils::constructPrevWordsInfo(env,
+    const NgramContext ngramContext = JniDataUtils::constructNgramContext(env,
             prevWordCodePointArrays, isBeginningOfSentenceArray, prevWordCount);
     if (givenSuggestOptions.isGesture() || inputSize > 0) {
         // TODO: Use SuggestionResults to return suggestions.
         dictionary->getSuggestions(pInfo, traverseSession, xCoordinates, yCoordinates,
-                times, pointerIds, inputCodePoints, inputSize, &prevWordsInfo,
+                times, pointerIds, inputCodePoints, inputSize, &ngramContext,
                 &givenSuggestOptions, weightOfLangModelVsSpatialModel, &suggestionResults);
     } else {
-        dictionary->getPredictions(&prevWordsInfo, &suggestionResults);
+        dictionary->getPredictions(&ngramContext, &suggestionResults);
     }
     if (DEBUG_DICT) {
         suggestionResults.dumpSuggestions();
@@ -289,10 +289,10 @@
     const jsize wordLength = env->GetArrayLength(word);
     int wordCodePoints[wordLength];
     env->GetIntArrayRegion(word, 0, wordLength, wordCodePoints);
-    const PrevWordsInfo prevWordsInfo = JniDataUtils::constructPrevWordsInfo(env,
+    const NgramContext ngramContext = JniDataUtils::constructNgramContext(env,
             prevWordCodePointArrays, isBeginningOfSentenceArray,
             env->GetArrayLength(prevWordCodePointArrays));
-    return dictionary->getNgramProbability(&prevWordsInfo,
+    return dictionary->getNgramProbability(&ngramContext,
             CodePointArrayView(wordCodePoints, wordLength));
 }
 
@@ -402,7 +402,7 @@
     if (!dictionary) {
         return false;
     }
-    const PrevWordsInfo prevWordsInfo = JniDataUtils::constructPrevWordsInfo(env,
+    const NgramContext ngramContext = JniDataUtils::constructNgramContext(env,
             prevWordCodePointArrays, isBeginningOfSentenceArray,
             env->GetArrayLength(prevWordCodePointArrays));
     jsize wordLength = env->GetArrayLength(word);
@@ -411,7 +411,7 @@
     // Use 1 for count to indicate the ngram has inputted.
     const NgramProperty ngramProperty(CodePointArrayView(wordCodePoints, wordLength).toVector(),
             probability, HistoricalInfo(timestamp, 0 /* level */, 1 /* count */));
-    return dictionary->addNgramEntry(&prevWordsInfo, &ngramProperty);
+    return dictionary->addNgramEntry(&ngramContext, &ngramProperty);
 }
 
 static bool latinime_BinaryDictionary_removeNgramEntry(JNIEnv *env, jclass clazz, jlong dict,
@@ -421,13 +421,13 @@
     if (!dictionary) {
         return false;
     }
-    const PrevWordsInfo prevWordsInfo = JniDataUtils::constructPrevWordsInfo(env,
+    const NgramContext ngramContext = JniDataUtils::constructNgramContext(env,
             prevWordCodePointArrays, isBeginningOfSentenceArray,
             env->GetArrayLength(prevWordCodePointArrays));
     jsize codePointCount = env->GetArrayLength(word);
     int wordCodePoints[codePointCount];
     env->GetIntArrayRegion(word, 0, codePointCount, wordCodePoints);
-    return dictionary->removeNgramEntry(&prevWordsInfo,
+    return dictionary->removeNgramEntry(&ngramContext,
             CodePointArrayView(wordCodePoints, codePointCount));
 }
 
@@ -439,14 +439,14 @@
     if (!dictionary) {
         return false;
     }
-    const PrevWordsInfo prevWordsInfo = JniDataUtils::constructPrevWordsInfo(env,
+    const NgramContext ngramContext = JniDataUtils::constructNgramContext(env,
             prevWordCodePointArrays, isBeginningOfSentenceArray,
             env->GetArrayLength(prevWordCodePointArrays));
     jsize codePointCount = env->GetArrayLength(word);
     int wordCodePoints[codePointCount];
     env->GetIntArrayRegion(word, 0, codePointCount, wordCodePoints);
     const HistoricalInfo historicalInfo(timestamp, 0 /* level */, count);
-    return dictionary->updateEntriesForWordWithNgramContext(&prevWordsInfo,
+    return dictionary->updateEntriesForWordWithNgramContext(&ngramContext,
             CodePointArrayView(wordCodePoints, codePointCount), isValidWord == JNI_TRUE,
             historicalInfo);
 }
@@ -529,9 +529,9 @@
             const NgramProperty ngramProperty(
                     CodePointArrayView(word1CodePoints, word1Length).toVector(),
                     bigramProbability, HistoricalInfo(timestamp, 0 /* level */, 1 /* count */));
-            const PrevWordsInfo prevWordsInfo(word0CodePoints, word0Length,
+            const NgramContext ngramContext(word0CodePoints, word0Length,
                     false /* isBeginningOfSentence */);
-            dictionary->addNgramEntry(&prevWordsInfo, &ngramProperty);
+            dictionary->addNgramEntry(&ngramContext, &ngramProperty);
         }
         if (dictionary->needsToRunGC(true /* mindsBlockByGC */)) {
             return i + 1;
@@ -641,10 +641,10 @@
                 return false;
             }
         }
-        const PrevWordsInfo prevWordsInfo(wordCodePoints, wordCodePointCount,
+        const NgramContext ngramContext(wordCodePoints, wordCodePointCount,
                 wordProperty.getUnigramProperty()->representsBeginningOfSentence());
         for (const NgramProperty &ngramProperty : *wordProperty.getNgramProperties()) {
-            if (!dictionaryStructureWithBufferPolicy->addNgramEntry(&prevWordsInfo,
+            if (!dictionaryStructureWithBufferPolicy->addNgramEntry(&ngramContext,
                     &ngramProperty)) {
                 LogUtils::logToJava(env, "Cannot add ngram to the new dict.");
                 return false;
diff --git a/native/jni/com_android_inputmethod_latin_DicTraverseSession.cpp b/native/jni/com_android_inputmethod_latin_DicTraverseSession.cpp
index 7660641..b664873 100644
--- a/native/jni/com_android_inputmethod_latin_DicTraverseSession.cpp
+++ b/native/jni/com_android_inputmethod_latin_DicTraverseSession.cpp
@@ -40,14 +40,14 @@
     }
     Dictionary *dict = reinterpret_cast<Dictionary *>(dictionary);
     if (!previousWord) {
-        PrevWordsInfo prevWordsInfo;
-        ts->init(dict, &prevWordsInfo, 0 /* suggestOptions */);
+        NgramContext emptyNgramContext;
+        ts->init(dict, &emptyNgramContext, 0 /* suggestOptions */);
         return;
     }
     int prevWord[previousWordLength];
     env->GetIntArrayRegion(previousWord, 0, previousWordLength, prevWord);
-    PrevWordsInfo prevWordsInfo(prevWord, previousWordLength, false /* isStartOfSentence */);
-    ts->init(dict, &prevWordsInfo, 0 /* suggestOptions */);
+    NgramContext ngramContext(prevWord, previousWordLength, false /* isStartOfSentence */);
+    ts->init(dict, &ngramContext, 0 /* suggestOptions */);
 }
 
 static void latinime_releaseDicTraverseSession(JNIEnv *env, jclass clazz, jlong traverseSession) {
diff --git a/native/jni/src/suggest/core/dictionary/dictionary.cpp b/native/jni/src/suggest/core/dictionary/dictionary.cpp
index bbd29c2..5d47994 100644
--- a/native/jni/src/suggest/core/dictionary/dictionary.cpp
+++ b/native/jni/src/suggest/core/dictionary/dictionary.cpp
@@ -46,11 +46,11 @@
 
 void Dictionary::getSuggestions(ProximityInfo *proximityInfo, DicTraverseSession *traverseSession,
         int *xcoordinates, int *ycoordinates, int *times, int *pointerIds, int *inputCodePoints,
-        int inputSize, const PrevWordsInfo *const prevWordsInfo,
+        int inputSize, const NgramContext *const ngramContext,
         const SuggestOptions *const suggestOptions, const float weightOfLangModelVsSpatialModel,
         SuggestionResults *const outSuggestionResults) const {
     TimeKeeper::setCurrentTime();
-    traverseSession->init(this, prevWordsInfo, suggestOptions);
+    traverseSession->init(this, ngramContext, suggestOptions);
     const auto &suggest = suggestOptions->isGesture() ? mGestureSuggest : mTypingSuggest;
     suggest->getSuggestions(proximityInfo, traverseSession, xcoordinates,
             ycoordinates, times, pointerIds, inputCodePoints, inputSize,
@@ -58,10 +58,10 @@
 }
 
 Dictionary::NgramListenerForPrediction::NgramListenerForPrediction(
-        const PrevWordsInfo *const prevWordsInfo, const WordIdArrayView prevWordIds,
+        const NgramContext *const ngramContext, const WordIdArrayView prevWordIds,
         SuggestionResults *const suggestionResults,
         const DictionaryStructureWithBufferPolicy *const dictStructurePolicy)
-    : mPrevWordsInfo(prevWordsInfo), mPrevWordIds(prevWordIds),
+    : mNgramContext(ngramContext), mPrevWordIds(prevWordIds),
       mSuggestionResults(suggestionResults), mDictStructurePolicy(dictStructurePolicy) {}
 
 void Dictionary::NgramListenerForPrediction::onVisitEntry(const int ngramProbability,
@@ -69,7 +69,7 @@
     if (targetWordId == NOT_A_WORD_ID) {
         return;
     }
-    if (mPrevWordsInfo->isNthPrevWordBeginningOfSentence(1 /* n */)
+    if (mNgramContext->isNthPrevWordBeginningOfSentence(1 /* n */)
             && ngramProbability == NOT_A_PROBABILITY) {
         return;
     }
@@ -85,20 +85,20 @@
             wordAttributes.getProbability());
 }
 
-void Dictionary::getPredictions(const PrevWordsInfo *const prevWordsInfo,
+void Dictionary::getPredictions(const NgramContext *const ngramContext,
         SuggestionResults *const outSuggestionResults) const {
     TimeKeeper::setCurrentTime();
     WordIdArray<MAX_PREV_WORD_COUNT_FOR_N_GRAM> prevWordIdArray;
-    const WordIdArrayView prevWordIds = prevWordsInfo->getPrevWordIds(
+    const WordIdArrayView prevWordIds = ngramContext->getPrevWordIds(
             mDictionaryStructureWithBufferPolicy.get(), &prevWordIdArray,
             true /* tryLowerCaseSearch */);
-    NgramListenerForPrediction listener(prevWordsInfo, prevWordIds, outSuggestionResults,
+    NgramListenerForPrediction listener(ngramContext, prevWordIds, outSuggestionResults,
             mDictionaryStructureWithBufferPolicy.get());
     mDictionaryStructureWithBufferPolicy->iterateNgramEntries(prevWordIds, &listener);
 }
 
 int Dictionary::getProbability(const CodePointArrayView codePoints) const {
-    return getNgramProbability(nullptr /* prevWordsInfo */, codePoints);
+    return getNgramProbability(nullptr /* ngramContext */, codePoints);
 }
 
 int Dictionary::getMaxProbabilityOfExactMatches(const CodePointArrayView codePoints) const {
@@ -107,18 +107,18 @@
             mDictionaryStructureWithBufferPolicy.get(), codePoints);
 }
 
-int Dictionary::getNgramProbability(const PrevWordsInfo *const prevWordsInfo,
+int Dictionary::getNgramProbability(const NgramContext *const ngramContext,
         const CodePointArrayView codePoints) const {
     TimeKeeper::setCurrentTime();
     const int wordId = mDictionaryStructureWithBufferPolicy->getWordId(codePoints,
             false /* forceLowerCaseSearch */);
     if (wordId == NOT_A_WORD_ID) return NOT_A_PROBABILITY;
-    if (!prevWordsInfo) {
+    if (!ngramContext) {
         return getDictionaryStructurePolicy()->getProbabilityOfWord(WordIdArrayView(), wordId);
     }
     WordIdArray<MAX_PREV_WORD_COUNT_FOR_N_GRAM> prevWordIdArray;
-    const WordIdArrayView prevWordIds = prevWordsInfo->getPrevWordIds
-            (mDictionaryStructureWithBufferPolicy.get(), &prevWordIdArray,
+    const WordIdArrayView prevWordIds = ngramContext->getPrevWordIds(
+            mDictionaryStructureWithBufferPolicy.get(), &prevWordIdArray,
             true /* tryLowerCaseSearch */);
     return getDictionaryStructurePolicy()->getProbabilityOfWord(prevWordIds, wordId);
 }
@@ -140,23 +140,23 @@
     return mDictionaryStructureWithBufferPolicy->removeUnigramEntry(codePoints);
 }
 
-bool Dictionary::addNgramEntry(const PrevWordsInfo *const prevWordsInfo,
+bool Dictionary::addNgramEntry(const NgramContext *const ngramContext,
         const NgramProperty *const ngramProperty) {
     TimeKeeper::setCurrentTime();
-    return mDictionaryStructureWithBufferPolicy->addNgramEntry(prevWordsInfo, ngramProperty);
+    return mDictionaryStructureWithBufferPolicy->addNgramEntry(ngramContext, ngramProperty);
 }
 
-bool Dictionary::removeNgramEntry(const PrevWordsInfo *const prevWordsInfo,
+bool Dictionary::removeNgramEntry(const NgramContext *const ngramContext,
         const CodePointArrayView codePoints) {
     TimeKeeper::setCurrentTime();
-    return mDictionaryStructureWithBufferPolicy->removeNgramEntry(prevWordsInfo, codePoints);
+    return mDictionaryStructureWithBufferPolicy->removeNgramEntry(ngramContext, codePoints);
 }
 
-bool Dictionary::updateEntriesForWordWithNgramContext(const PrevWordsInfo *const prevWordsInfo,
+bool Dictionary::updateEntriesForWordWithNgramContext(const NgramContext *const ngramContext,
         const CodePointArrayView codePoints, const bool isValidWord,
         const HistoricalInfo historicalInfo) {
     TimeKeeper::setCurrentTime();
-    return mDictionaryStructureWithBufferPolicy->updateEntriesForWordWithNgramContext(prevWordsInfo,
+    return mDictionaryStructureWithBufferPolicy->updateEntriesForWordWithNgramContext(ngramContext,
             codePoints, isValidWord, historicalInfo);
 }
 
diff --git a/native/jni/src/suggest/core/dictionary/dictionary.h b/native/jni/src/suggest/core/dictionary/dictionary.h
index 1401e76..843aec4 100644
--- a/native/jni/src/suggest/core/dictionary/dictionary.h
+++ b/native/jni/src/suggest/core/dictionary/dictionary.h
@@ -33,7 +33,7 @@
 
 class DictionaryStructureWithBufferPolicy;
 class DicTraverseSession;
-class PrevWordsInfo;
+class NgramContext;
 class ProximityInfo;
 class SuggestionResults;
 class SuggestOptions;
@@ -66,18 +66,18 @@
 
     void getSuggestions(ProximityInfo *proximityInfo, DicTraverseSession *traverseSession,
             int *xcoordinates, int *ycoordinates, int *times, int *pointerIds, int *inputCodePoints,
-            int inputSize, const PrevWordsInfo *const prevWordsInfo,
+            int inputSize, const NgramContext *const ngramContext,
             const SuggestOptions *const suggestOptions, const float weightOfLangModelVsSpatialModel,
             SuggestionResults *const outSuggestionResults) const;
 
-    void getPredictions(const PrevWordsInfo *const prevWordsInfo,
+    void getPredictions(const NgramContext *const ngramContext,
             SuggestionResults *const outSuggestionResults) const;
 
     int getProbability(const CodePointArrayView codePoints) const;
 
     int getMaxProbabilityOfExactMatches(const CodePointArrayView codePoints) const;
 
-    int getNgramProbability(const PrevWordsInfo *const prevWordsInfo,
+    int getNgramProbability(const NgramContext *const ngramContext,
             const CodePointArrayView codePoints) const;
 
     bool addUnigramEntry(const CodePointArrayView codePoints,
@@ -85,13 +85,13 @@
 
     bool removeUnigramEntry(const CodePointArrayView codePoints);
 
-    bool addNgramEntry(const PrevWordsInfo *const prevWordsInfo,
+    bool addNgramEntry(const NgramContext *const ngramContext,
             const NgramProperty *const ngramProperty);
 
-    bool removeNgramEntry(const PrevWordsInfo *const prevWordsInfo,
+    bool removeNgramEntry(const NgramContext *const ngramContext,
             const CodePointArrayView codePoints);
 
-    bool updateEntriesForWordWithNgramContext(const PrevWordsInfo *const prevWordsInfo,
+    bool updateEntriesForWordWithNgramContext(const NgramContext *const ngramContext,
             const CodePointArrayView codePoints, const bool isValidWord,
             const HistoricalInfo historicalInfo);
 
@@ -123,7 +123,7 @@
 
     class NgramListenerForPrediction : public NgramListener {
      public:
-        NgramListenerForPrediction(const PrevWordsInfo *const prevWordsInfo,
+        NgramListenerForPrediction(const NgramContext *const ngramContext,
                 const WordIdArrayView prevWordIds, SuggestionResults *const suggestionResults,
                 const DictionaryStructureWithBufferPolicy *const dictStructurePolicy);
         virtual void onVisitEntry(const int ngramProbability, const int targetWordId);
@@ -131,7 +131,7 @@
      private:
         DISALLOW_IMPLICIT_CONSTRUCTORS(NgramListenerForPrediction);
 
-        const PrevWordsInfo *const mPrevWordsInfo;
+        const NgramContext *const mNgramContext;
         const WordIdArrayView mPrevWordIds;
         SuggestionResults *const mSuggestionResults;
         const DictionaryStructureWithBufferPolicy *const mDictStructurePolicy;
diff --git a/native/jni/src/suggest/core/dictionary/dictionary_utils.cpp b/native/jni/src/suggest/core/dictionary/dictionary_utils.cpp
index b85f362..e3e9c92 100644
--- a/native/jni/src/suggest/core/dictionary/dictionary_utils.cpp
+++ b/native/jni/src/suggest/core/dictionary/dictionary_utils.cpp
@@ -33,10 +33,10 @@
     std::vector<DicNode> current;
     std::vector<DicNode> next;
 
-    // No prev words information.
-    PrevWordsInfo emptyPrevWordsInfo;
+    // No ngram context.
+    NgramContext emptyNgramContext;
     WordIdArray<MAX_PREV_WORD_COUNT_FOR_N_GRAM> prevWordIdArray;
-    const WordIdArrayView prevWordIds = emptyPrevWordsInfo.getPrevWordIds(
+    const WordIdArrayView prevWordIds = emptyNgramContext.getPrevWordIds(
             dictionaryStructurePolicy, &prevWordIdArray, false /* tryLowerCaseSearch */);
     current.emplace_back();
     DicNodeUtils::initAsRoot(dictionaryStructurePolicy, prevWordIds, &current.front());
diff --git a/native/jni/src/suggest/core/policy/dictionary_structure_with_buffer_policy.h b/native/jni/src/suggest/core/policy/dictionary_structure_with_buffer_policy.h
index 02df348..ceda5c0 100644
--- a/native/jni/src/suggest/core/policy/dictionary_structure_with_buffer_policy.h
+++ b/native/jni/src/suggest/core/policy/dictionary_structure_with_buffer_policy.h
@@ -33,7 +33,7 @@
 class DictionaryHeaderStructurePolicy;
 class MultiBigramMap;
 class NgramListener;
-class PrevWordsInfo;
+class NgramContext;
 class UnigramProperty;
 
 /*
@@ -81,15 +81,15 @@
     virtual bool removeUnigramEntry(const CodePointArrayView wordCodePoints) = 0;
 
     // Returns whether the update was success or not.
-    virtual bool addNgramEntry(const PrevWordsInfo *const prevWordsInfo,
+    virtual bool addNgramEntry(const NgramContext *const ngramContext,
             const NgramProperty *const ngramProperty) = 0;
 
     // Returns whether the update was success or not.
-    virtual bool removeNgramEntry(const PrevWordsInfo *const prevWordsInfo,
+    virtual bool removeNgramEntry(const NgramContext *const ngramContext,
             const CodePointArrayView wordCodePoints) = 0;
 
     // Returns whether the update was success or not.
-    virtual bool updateEntriesForWordWithNgramContext(const PrevWordsInfo *const prevWordsInfo,
+    virtual bool updateEntriesForWordWithNgramContext(const NgramContext *const ngramContext,
             const CodePointArrayView wordCodePoints, const bool isValidWord,
             const HistoricalInfo historicalInfo) = 0;
 
diff --git a/native/jni/src/suggest/core/session/dic_traverse_session.cpp b/native/jni/src/suggest/core/session/dic_traverse_session.cpp
index b4d01d0..d0e7d0d 100644
--- a/native/jni/src/suggest/core/session/dic_traverse_session.cpp
+++ b/native/jni/src/suggest/core/session/dic_traverse_session.cpp
@@ -30,12 +30,12 @@
         256 * 1024;
 
 void DicTraverseSession::init(const Dictionary *const dictionary,
-        const PrevWordsInfo *const prevWordsInfo, const SuggestOptions *const suggestOptions) {
+        const NgramContext *const ngramContext, const SuggestOptions *const suggestOptions) {
     mDictionary = dictionary;
     mMultiWordCostMultiplier = getDictionaryStructurePolicy()->getHeaderStructurePolicy()
             ->getMultiWordCostMultiplier();
     mSuggestOptions = suggestOptions;
-    mPrevWordIdCount = prevWordsInfo->getPrevWordIds(getDictionaryStructurePolicy(),
+    mPrevWordIdCount = ngramContext->getPrevWordIds(getDictionaryStructurePolicy(),
             &mPrevWordIdArray, true /* tryLowerCaseSearch */).size();
 }
 
diff --git a/native/jni/src/suggest/core/session/dic_traverse_session.h b/native/jni/src/suggest/core/session/dic_traverse_session.h
index 9f841aa..bc53167 100644
--- a/native/jni/src/suggest/core/session/dic_traverse_session.h
+++ b/native/jni/src/suggest/core/session/dic_traverse_session.h
@@ -30,7 +30,7 @@
 
 class Dictionary;
 class DictionaryStructureWithBufferPolicy;
-class PrevWordsInfo;
+class NgramContext;
 class ProximityInfo;
 class SuggestOptions;
 
@@ -61,7 +61,7 @@
     // Non virtual inline destructor -- never inherit this class
     AK_FORCE_INLINE ~DicTraverseSession() {}
 
-    void init(const Dictionary *dictionary, const PrevWordsInfo *const prevWordsInfo,
+    void init(const Dictionary *dictionary, const NgramContext *const ngramContext,
             const SuggestOptions *const suggestOptions);
     // TODO: Remove and merge into init
     void setupForGetSuggestions(const ProximityInfo *pInfo, const int *inputCodePoints,
diff --git a/native/jni/src/suggest/core/session/prev_words_info.h b/native/jni/src/suggest/core/session/prev_words_info.h
index 48ca0e2..64c7141 100644
--- a/native/jni/src/suggest/core/session/prev_words_info.h
+++ b/native/jni/src/suggest/core/session/prev_words_info.h
@@ -14,8 +14,8 @@
  * limitations under the License.
  */
 
-#ifndef LATINIME_PREV_WORDS_INFO_H
-#define LATINIME_PREV_WORDS_INFO_H
+#ifndef LATINIME_NGRAM_CONTEXT_H
+#define LATINIME_NGRAM_CONTEXT_H
 
 #include <array>
 
@@ -27,25 +27,25 @@
 namespace latinime {
 
 // Rename to NgramContext.
-class PrevWordsInfo {
+class NgramContext {
  public:
     // No prev word information.
-    PrevWordsInfo() : mPrevWordCount(0) {
+    NgramContext() : mPrevWordCount(0) {
         clear();
     }
 
-    PrevWordsInfo(const PrevWordsInfo &prevWordsInfo)
-            : mPrevWordCount(prevWordsInfo.mPrevWordCount) {
+    NgramContext(const NgramContext &ngramContext)
+            : mPrevWordCount(ngramContext.mPrevWordCount) {
         for (size_t i = 0; i < mPrevWordCount; ++i) {
-            mPrevWordCodePointCount[i] = prevWordsInfo.mPrevWordCodePointCount[i];
-            memmove(mPrevWordCodePoints[i], prevWordsInfo.mPrevWordCodePoints[i],
+            mPrevWordCodePointCount[i] = ngramContext.mPrevWordCodePointCount[i];
+            memmove(mPrevWordCodePoints[i], ngramContext.mPrevWordCodePoints[i],
                     sizeof(mPrevWordCodePoints[i][0]) * mPrevWordCodePointCount[i]);
-            mIsBeginningOfSentence[i] = prevWordsInfo.mIsBeginningOfSentence[i];
+            mIsBeginningOfSentence[i] = ngramContext.mIsBeginningOfSentence[i];
         }
     }
 
     // Construct from previous words.
-    PrevWordsInfo(const int prevWordCodePoints[][MAX_WORD_LENGTH],
+    NgramContext(const int prevWordCodePoints[][MAX_WORD_LENGTH],
             const int *const prevWordCodePointCount, const bool *const isBeginningOfSentence,
             const size_t prevWordCount)
             : mPrevWordCount(std::min(NELEMS(mPrevWordCodePoints), prevWordCount)) {
@@ -62,7 +62,7 @@
     }
 
     // Construct from a previous word.
-    PrevWordsInfo(const int *const prevWordCodePoints, const int prevWordCodePointCount,
+    NgramContext(const int *const prevWordCodePoints, const int prevWordCodePointCount,
             const bool isBeginningOfSentence) : mPrevWordCount(1) {
         clear();
         if (prevWordCodePointCount > MAX_WORD_LENGTH || !prevWordCodePoints) {
@@ -79,8 +79,8 @@
     }
 
     // TODO: Remove.
-    const PrevWordsInfo getTrimmedPrevWordsInfo(const size_t maxPrevWordCount) const {
-        return PrevWordsInfo(mPrevWordCodePoints, mPrevWordCodePointCount, mIsBeginningOfSentence,
+    const NgramContext getTrimmedNgramContext(const size_t maxPrevWordCount) const {
+        return NgramContext(mPrevWordCodePoints, mPrevWordCodePointCount, mIsBeginningOfSentence,
                 std::min(mPrevWordCount, maxPrevWordCount));
     }
 
@@ -123,7 +123,7 @@
     }
 
  private:
-    DISALLOW_ASSIGNMENT_OPERATOR(PrevWordsInfo);
+    DISALLOW_ASSIGNMENT_OPERATOR(NgramContext);
 
     static int getWordId(const DictionaryStructureWithBufferPolicy *const dictStructurePolicy,
             const int *const wordCodePoints, const int wordCodePointCount,
@@ -166,4 +166,4 @@
     bool mIsBeginningOfSentence[MAX_PREV_WORD_COUNT_FOR_N_GRAM];
 };
 } // namespace latinime
-#endif // LATINIME_PREV_WORDS_INFO_H
+#endif // LATINIME_NGRAM_CONTEXT_H
diff --git a/native/jni/src/suggest/policyimpl/dictionary/structure/backward/v402/ver4_patricia_trie_policy.cpp b/native/jni/src/suggest/policyimpl/dictionary/structure/backward/v402/ver4_patricia_trie_policy.cpp
index 8e78ea5..6ae44ec 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/structure/backward/v402/ver4_patricia_trie_policy.cpp
+++ b/native/jni/src/suggest/policyimpl/dictionary/structure/backward/v402/ver4_patricia_trie_policy.cpp
@@ -338,7 +338,7 @@
     return mNodeWriter.suppressUnigramEntry(&ptNodeParams);
 }
 
-bool Ver4PatriciaTriePolicy::addNgramEntry(const PrevWordsInfo *const prevWordsInfo,
+bool Ver4PatriciaTriePolicy::addNgramEntry(const NgramContext *const ngramContext,
         const NgramProperty *const ngramProperty) {
     if (!mBuffers->isUpdatable()) {
         AKLOGI("Warning: addNgramEntry() is called for non-updatable dictionary.");
@@ -349,8 +349,8 @@
                 mDictBuffer->getTailPosition());
         return false;
     }
-    if (!prevWordsInfo->isValid()) {
-        AKLOGE("prev words info is not valid for adding n-gram entry to the dictionary.");
+    if (!ngramContext->isValid()) {
+        AKLOGE("Ngram context is not valid for adding n-gram entry to the dictionary.");
         return false;
     }
     if (ngramProperty->getTargetCodePoints()->size() > MAX_WORD_LENGTH) {
@@ -359,23 +359,23 @@
         return false;
     }
     WordIdArray<MAX_PREV_WORD_COUNT_FOR_N_GRAM> prevWordIdArray;
-    const WordIdArrayView prevWordIds = prevWordsInfo->getPrevWordIds(this, &prevWordIdArray,
+    const WordIdArrayView prevWordIds = ngramContext->getPrevWordIds(this, &prevWordIdArray,
             false /* tryLowerCaseSearch */);
     if (prevWordIds.empty()) {
         return false;
     }
     if (prevWordIds[0] == NOT_A_WORD_ID) {
-        if (prevWordsInfo->isNthPrevWordBeginningOfSentence(1 /* n */)) {
+        if (ngramContext->isNthPrevWordBeginningOfSentence(1 /* n */)) {
             const UnigramProperty beginningOfSentenceUnigramProperty(
                     true /* representsBeginningOfSentence */, true /* isNotAWord */,
                     false /* isBlacklisted */, MAX_PROBABILITY /* probability */, HistoricalInfo());
-            if (!addUnigramEntry(prevWordsInfo->getNthPrevWordCodePoints(1 /* n */),
+            if (!addUnigramEntry(ngramContext->getNthPrevWordCodePoints(1 /* n */),
                     &beginningOfSentenceUnigramProperty)) {
                 AKLOGE("Cannot add unigram entry for the beginning-of-sentence.");
                 return false;
             }
             // Refresh word ids.
-            prevWordsInfo->getPrevWordIds(this, &prevWordIdArray, false /* tryLowerCaseSearch */);
+            ngramContext->getPrevWordIds(this, &prevWordIdArray, false /* tryLowerCaseSearch */);
         } else {
             return false;
         }
@@ -399,7 +399,7 @@
     }
 }
 
-bool Ver4PatriciaTriePolicy::removeNgramEntry(const PrevWordsInfo *const prevWordsInfo,
+bool Ver4PatriciaTriePolicy::removeNgramEntry(const NgramContext *const ngramContext,
         const CodePointArrayView wordCodePoints) {
     if (!mBuffers->isUpdatable()) {
         AKLOGI("Warning: removeNgramEntry() is called for non-updatable dictionary.");
@@ -410,8 +410,8 @@
                 mDictBuffer->getTailPosition());
         return false;
     }
-    if (!prevWordsInfo->isValid()) {
-        AKLOGE("prev words info is not valid for removing n-gram entry form the dictionary.");
+    if (!ngramContext->isValid()) {
+        AKLOGE("Ngram context is not valid for removing n-gram entry form the dictionary.");
         return false;
     }
     if (wordCodePoints.size() > MAX_WORD_LENGTH) {
@@ -419,7 +419,7 @@
                 wordCodePoints.size());
     }
     WordIdArray<MAX_PREV_WORD_COUNT_FOR_N_GRAM> prevWordIdArray;
-    const WordIdArrayView prevWordIds = prevWordsInfo->getPrevWordIds(this, &prevWordIdArray,
+    const WordIdArrayView prevWordIds = ngramContext->getPrevWordIds(this, &prevWordIdArray,
             false /* tryLowerCaseSerch */);
     if (prevWordIds.firstOrDefault(NOT_A_WORD_ID) == NOT_A_WORD_ID) {
         return false;
@@ -441,7 +441,7 @@
 
 
 bool Ver4PatriciaTriePolicy::updateEntriesForWordWithNgramContext(
-        const PrevWordsInfo *const prevWordsInfo, const CodePointArrayView wordCodePoints,
+        const NgramContext *const ngramContext, const CodePointArrayView wordCodePoints,
         const bool isValidWord, const HistoricalInfo historicalInfo) {
     if (!mBuffers->isUpdatable()) {
         AKLOGI("Warning: updateEntriesForWordWithNgramContext() is called for non-updatable "
@@ -455,11 +455,11 @@
         AKLOGE("Cannot update unigarm entry in updateEntriesForWordWithNgramContext().");
         return false;
     }
-    const int probabilityForNgram = prevWordsInfo->isNthPrevWordBeginningOfSentence(1 /* n */)
+    const int probabilityForNgram = ngramContext->isNthPrevWordBeginningOfSentence(1 /* n */)
             ? NOT_A_PROBABILITY : probability;
     const NgramProperty ngramProperty(wordCodePoints.toVector(), probabilityForNgram,
             historicalInfo);
-    if (!addNgramEntry(prevWordsInfo, &ngramProperty)) {
+    if (!addNgramEntry(ngramContext, &ngramProperty)) {
         AKLOGE("Cannot update unigarm entry in updateEntriesForWordWithNgramContext().");
         return false;
     }
diff --git a/native/jni/src/suggest/policyimpl/dictionary/structure/backward/v402/ver4_patricia_trie_policy.h b/native/jni/src/suggest/policyimpl/dictionary/structure/backward/v402/ver4_patricia_trie_policy.h
index e4d7ff1..4aa399c 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/structure/backward/v402/ver4_patricia_trie_policy.h
+++ b/native/jni/src/suggest/policyimpl/dictionary/structure/backward/v402/ver4_patricia_trie_policy.h
@@ -112,13 +112,13 @@
 
     bool removeUnigramEntry(const CodePointArrayView wordCodePoints);
 
-    bool addNgramEntry(const PrevWordsInfo *const prevWordsInfo,
+    bool addNgramEntry(const NgramContext *const ngramContext,
             const NgramProperty *const ngramProperty);
 
-    bool removeNgramEntry(const PrevWordsInfo *const prevWordsInfo,
+    bool removeNgramEntry(const NgramContext *const ngramContext,
             const CodePointArrayView wordCodePoints);
 
-    bool updateEntriesForWordWithNgramContext(const PrevWordsInfo *const prevWordsInfo,
+    bool updateEntriesForWordWithNgramContext(const NgramContext *const ngramContext,
             const CodePointArrayView wordCodePoints, const bool isValidWord,
             const HistoricalInfo historicalInfo);
 
diff --git a/native/jni/src/suggest/policyimpl/dictionary/structure/v2/patricia_trie_policy.h b/native/jni/src/suggest/policyimpl/dictionary/structure/v2/patricia_trie_policy.h
index 16aa592..b176813 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/structure/v2/patricia_trie_policy.h
+++ b/native/jni/src/suggest/policyimpl/dictionary/structure/v2/patricia_trie_policy.h
@@ -93,21 +93,21 @@
         return false;
     }
 
-    bool addNgramEntry(const PrevWordsInfo *const prevWordsInfo,
+    bool addNgramEntry(const NgramContext *const ngramContext,
             const NgramProperty *const ngramProperty) {
         // This method should not be called for non-updatable dictionary.
         AKLOGI("Warning: addNgramEntry() is called for non-updatable dictionary.");
         return false;
     }
 
-    bool removeNgramEntry(const PrevWordsInfo *const prevWordsInfo,
+    bool removeNgramEntry(const NgramContext *const ngramContext,
             const CodePointArrayView wordCodePoints) {
         // This method should not be called for non-updatable dictionary.
         AKLOGI("Warning: removeNgramEntry() is called for non-updatable dictionary.");
         return false;
     }
 
-    bool updateEntriesForWordWithNgramContext(const PrevWordsInfo *const prevWordsInfo,
+    bool updateEntriesForWordWithNgramContext(const NgramContext *const ngramContext,
             const CodePointArrayView wordCodePoints, const bool isValidWord,
             const HistoricalInfo historicalInfo) {
         // This method should not be called for non-updatable dictionary.
diff --git a/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_patricia_trie_policy.cpp b/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_patricia_trie_policy.cpp
index 76377a2..69dcf34 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_patricia_trie_policy.cpp
+++ b/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_patricia_trie_policy.cpp
@@ -266,7 +266,7 @@
     return true;
 }
 
-bool Ver4PatriciaTriePolicy::addNgramEntry(const PrevWordsInfo *const prevWordsInfo,
+bool Ver4PatriciaTriePolicy::addNgramEntry(const NgramContext *const ngramContext,
         const NgramProperty *const ngramProperty) {
     if (!mBuffers->isUpdatable()) {
         AKLOGI("Warning: addNgramEntry() is called for non-updatable dictionary.");
@@ -277,8 +277,8 @@
                 mDictBuffer->getTailPosition());
         return false;
     }
-    if (!prevWordsInfo->isValid()) {
-        AKLOGE("prev words info is not valid for adding n-gram entry to the dictionary.");
+    if (!ngramContext->isValid()) {
+        AKLOGE("Ngram context is not valid for adding n-gram entry to the dictionary.");
         return false;
     }
     if (ngramProperty->getTargetCodePoints()->size() > MAX_WORD_LENGTH) {
@@ -287,7 +287,7 @@
         return false;
     }
     WordIdArray<MAX_PREV_WORD_COUNT_FOR_N_GRAM> prevWordIdArray;
-    const WordIdArrayView prevWordIds = prevWordsInfo->getPrevWordIds(this, &prevWordIdArray,
+    const WordIdArrayView prevWordIds = ngramContext->getPrevWordIds(this, &prevWordIdArray,
             false /* tryLowerCaseSearch */);
     if (prevWordIds.empty()) {
         return false;
@@ -296,19 +296,19 @@
         if (prevWordIds[i] != NOT_A_WORD_ID) {
             continue;
         }
-        if (!prevWordsInfo->isNthPrevWordBeginningOfSentence(i + 1 /* n */)) {
+        if (!ngramContext->isNthPrevWordBeginningOfSentence(i + 1 /* n */)) {
             return false;
         }
         const UnigramProperty beginningOfSentenceUnigramProperty(
                 true /* representsBeginningOfSentence */, true /* isNotAWord */,
                 false /* isBlacklisted */, MAX_PROBABILITY /* probability */, HistoricalInfo());
-        if (!addUnigramEntry(prevWordsInfo->getNthPrevWordCodePoints(1 /* n */),
+        if (!addUnigramEntry(ngramContext->getNthPrevWordCodePoints(1 /* n */),
                 &beginningOfSentenceUnigramProperty)) {
             AKLOGE("Cannot add unigram entry for the beginning-of-sentence.");
             return false;
         }
         // Refresh word ids.
-        prevWordsInfo->getPrevWordIds(this, &prevWordIdArray, false /* tryLowerCaseSearch */);
+        ngramContext->getPrevWordIds(this, &prevWordIdArray, false /* tryLowerCaseSearch */);
     }
     const int wordId = getWordId(CodePointArrayView(*ngramProperty->getTargetCodePoints()),
             false /* forceLowerCaseSearch */);
@@ -326,7 +326,7 @@
     }
 }
 
-bool Ver4PatriciaTriePolicy::removeNgramEntry(const PrevWordsInfo *const prevWordsInfo,
+bool Ver4PatriciaTriePolicy::removeNgramEntry(const NgramContext *const ngramContext,
         const CodePointArrayView wordCodePoints) {
     if (!mBuffers->isUpdatable()) {
         AKLOGI("Warning: removeNgramEntry() is called for non-updatable dictionary.");
@@ -337,8 +337,8 @@
                 mDictBuffer->getTailPosition());
         return false;
     }
-    if (!prevWordsInfo->isValid()) {
-        AKLOGE("prev words info is not valid for removing n-gram entry form the dictionary.");
+    if (!ngramContext->isValid()) {
+        AKLOGE("Ngram context is not valid for removing n-gram entry form the dictionary.");
         return false;
     }
     if (wordCodePoints.size() > MAX_WORD_LENGTH) {
@@ -346,7 +346,7 @@
                 wordCodePoints.size());
     }
     WordIdArray<MAX_PREV_WORD_COUNT_FOR_N_GRAM> prevWordIdArray;
-    const WordIdArrayView prevWordIds = prevWordsInfo->getPrevWordIds(this, &prevWordIdArray,
+    const WordIdArrayView prevWordIds = ngramContext->getPrevWordIds(this, &prevWordIdArray,
             false /* tryLowerCaseSerch */);
     if (prevWordIds.empty() || prevWordIds.contains(NOT_A_WORD_ID)) {
         return false;
@@ -364,7 +364,7 @@
 }
 
 bool Ver4PatriciaTriePolicy::updateEntriesForWordWithNgramContext(
-        const PrevWordsInfo *const prevWordsInfo, const CodePointArrayView wordCodePoints,
+        const NgramContext *const ngramContext, const CodePointArrayView wordCodePoints,
         const bool isValidWord, const HistoricalInfo historicalInfo) {
     if (!mBuffers->isUpdatable()) {
         AKLOGI("Warning: updateEntriesForWordWithNgramContext() is called for non-updatable "
@@ -379,13 +379,13 @@
         AKLOGE("Cannot update unigarm entry in updateEntriesForWordWithNgramContext().");
         return false;
     }
-    const int probabilityForNgram = prevWordsInfo->isNthPrevWordBeginningOfSentence(1 /* n */)
+    const int probabilityForNgram = ngramContext->isNthPrevWordBeginningOfSentence(1 /* n */)
             ? NOT_A_PROBABILITY : probability;
     const NgramProperty ngramProperty(wordCodePoints.toVector(), probabilityForNgram,
             historicalInfo);
-    for (size_t i = 1; i <= prevWordsInfo->getPrevWordCount(); ++i) {
-        const PrevWordsInfo trimmedPrevWordsInfo(prevWordsInfo->getTrimmedPrevWordsInfo(i));
-        if (!addNgramEntry(&trimmedPrevWordsInfo, &ngramProperty)) {
+    for (size_t i = 1; i <= ngramContext->getPrevWordCount(); ++i) {
+        const NgramContext trimmedNgramContext(ngramContext->getTrimmedNgramContext(i));
+        if (!addNgramEntry(&trimmedNgramContext, &ngramProperty)) {
             AKLOGE("Cannot update ngram entry in updateEntriesForWordWithNgramContext().");
             return false;
         }
diff --git a/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_patricia_trie_policy.h b/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_patricia_trie_policy.h
index 696ec1f..60e30f2 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_patricia_trie_policy.h
+++ b/native/jni/src/suggest/policyimpl/dictionary/structure/v4/ver4_patricia_trie_policy.h
@@ -92,13 +92,13 @@
 
     bool removeUnigramEntry(const CodePointArrayView wordCodePoints);
 
-    bool addNgramEntry(const PrevWordsInfo *const prevWordsInfo,
+    bool addNgramEntry(const NgramContext *const ngramContext,
             const NgramProperty *const ngramProperty);
 
-    bool removeNgramEntry(const PrevWordsInfo *const prevWordsInfo,
+    bool removeNgramEntry(const NgramContext *const ngramContext,
             const CodePointArrayView wordCodePoints);
 
-    bool updateEntriesForWordWithNgramContext(const PrevWordsInfo *const prevWordsInfo,
+    bool updateEntriesForWordWithNgramContext(const NgramContext *const ngramContext,
             const CodePointArrayView wordCodePoints, const bool isValidWord,
             const HistoricalInfo historicalInfo);
 
diff --git a/native/jni/src/utils/jni_data_utils.h b/native/jni/src/utils/jni_data_utils.h
index 235a03b..21611fd 100644
--- a/native/jni/src/utils/jni_data_utils.h
+++ b/native/jni/src/utils/jni_data_utils.h
@@ -96,7 +96,7 @@
         }
     }
 
-    static PrevWordsInfo constructPrevWordsInfo(JNIEnv *env, jobjectArray prevWordCodePointArrays,
+    static NgramContext constructNgramContext(JNIEnv *env, jobjectArray prevWordCodePointArrays,
             jbooleanArray isBeginningOfSentenceArray, const size_t prevWordCount) {
         int prevWordCodePoints[MAX_PREV_WORD_COUNT_FOR_N_GRAM][MAX_WORD_LENGTH];
         int prevWordCodePointCount[MAX_PREV_WORD_COUNT_FOR_N_GRAM];
@@ -119,7 +119,7 @@
                     &isBeginningOfSentenceBoolean);
             isBeginningOfSentence[i] = isBeginningOfSentenceBoolean == JNI_TRUE;
         }
-        return PrevWordsInfo(prevWordCodePoints, prevWordCodePointCount, isBeginningOfSentence,
+        return NgramContext(prevWordCodePoints, prevWordCodePointCount, isBeginningOfSentence,
                 prevWordCount);
     }