diff --git a/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_reading_helper.cpp b/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_reading_helper.cpp
index a2712c3..a0b5be6 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_reading_helper.cpp
+++ b/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_reading_helper.cpp
@@ -70,6 +70,7 @@
     if (usesAdditionalBuffer) {
         mPos += mBuffer->getOriginalBufferSize();
     }
+    mPosOfLastForwardLinkField = mPos;
     if (DynamicPatriciaTrieReadingUtils::isValidForwardLinkPosition(forwardLinkPosition)) {
         // Follow the forward link.
         mPos += forwardLinkPosition;
diff --git a/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_reading_helper.h b/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_reading_helper.h
index b108ed5..db1c392 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_reading_helper.h
+++ b/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_reading_helper.h
@@ -38,8 +38,8 @@
             const DictionaryBigramsStructurePolicy *const bigramsPolicy,
             const DictionaryShortcutsStructurePolicy *const shortcutsPolicy)
             : mIsError(false), mPos(NOT_A_DICT_POS), mNodeCount(0), mPrevTotalCodePointCount(0),
-              mTotalNodeCount(0), mNodeArrayCount(0), mBuffer(buffer),
-              mNodeReader(mBuffer, bigramsPolicy, shortcutsPolicy) {}
+              mTotalNodeCount(0), mNodeArrayCount(0), mPosOfLastForwardLinkField(NOT_A_DICT_POS),
+              mBuffer(buffer), mNodeReader(mBuffer, bigramsPolicy, shortcutsPolicy) {}
 
     ~DynamicPatriciaTrieReadingHelper() {}
 
@@ -62,6 +62,7 @@
             mPrevTotalCodePointCount = 0;
             mTotalNodeCount = 0;
             mNodeArrayCount = 0;
+            mPosOfLastForwardLinkField = NOT_A_DICT_POS;
             nextNodeArray();
             if (!isEnd()) {
                 fetchNodeInfo();
@@ -81,6 +82,7 @@
             mPrevTotalCodePointCount = 0;
             mTotalNodeCount = 1;
             mNodeArrayCount = 1;
+            mPosOfLastForwardLinkField = NOT_A_DICT_POS;
             fetchNodeInfo();
         }
     }
@@ -140,6 +142,7 @@
             mTotalNodeCount = 0;
             mNodeArrayCount = 0;
             mPos = mNodeReader.getChildrenPos();
+            mPosOfLastForwardLinkField = NOT_A_DICT_POS;
             // Read children node array.
             nextNodeArray();
             if (!isEnd()) {
@@ -158,12 +161,17 @@
             mNodeArrayCount = 1;
             mNodeCount = 1;
             mPos = mNodeReader.getParentPos();
+            mPosOfLastForwardLinkField = NOT_A_DICT_POS;
             fetchNodeInfo();
         } else {
             mPos = NOT_A_DICT_POS;
         }
     }
 
+    AK_FORCE_INLINE int getPosOfLastForwardLinkField() const {
+        return mPosOfLastForwardLinkField;
+    }
+
  private:
     DISALLOW_COPY_AND_ASSIGN(DynamicPatriciaTrieReadingHelper);
 
@@ -177,6 +185,7 @@
     int mPrevTotalCodePointCount;
     int mTotalNodeCount;
     int mNodeArrayCount;
+    int mPosOfLastForwardLinkField;
     const BufferWithExtendableBuffer *const mBuffer;
     DynamicPatriciaTrieNodeReader mNodeReader;
     int mMergedNodeCodePoints[MAX_WORD_LENGTH];
diff --git a/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_writing_helper.cpp b/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_writing_helper.cpp
index a4793e1..03dc576 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_writing_helper.cpp
+++ b/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_writing_helper.cpp
@@ -19,7 +19,9 @@
 #include "suggest/policyimpl/dictionary/bigram/dynamic_bigram_list_policy.h"
 #include "suggest/policyimpl/dictionary/dynamic_patricia_trie_node_reader.h"
 #include "suggest/policyimpl/dictionary/dynamic_patricia_trie_reading_helper.h"
+#include "suggest/policyimpl/dictionary/dynamic_patricia_trie_reading_utils.h"
 #include "suggest/policyimpl/dictionary/dynamic_patricia_trie_writing_utils.h"
+#include "suggest/policyimpl/dictionary/patricia_trie_reading_utils.h"
 #include "suggest/policyimpl/dictionary/shortcut/dynamic_shortcut_list_policy.h"
 
 namespace latinime {
@@ -27,6 +29,7 @@
 bool DynamicPatriciaTrieWritingHelper::addUnigramWord(
         DynamicPatriciaTrieReadingHelper *const readingHelper,
         const int *const wordCodePoints, const int codePointCount, const int probability) {
+    int parentPos = NOT_A_VALID_WORD_POS;
     while (!readingHelper->isEnd()) {
         const int matchedCodePointCount = readingHelper->getPrevTotalCodePointCount();
         if (!readingHelper->isMatchedCodePoint(0 /* index */,
@@ -65,14 +68,20 @@
             return false;
         }
         // Advance to the children nodes.
+        parentPos = nodeReader->getNodePos();
         readingHelper->readChildNode();
     }
     if (readingHelper->isError()) {
         // The dictionary is invalid.
         return false;
     }
-    // TODO: add at the last position of the node array.
+    int pos = readingHelper->getPosOfLastForwardLinkField();
+    // TODO: Remove.
     return false;
+    return createAndInsertNodeIntoPtNodeArray(parentPos,
+            wordCodePoints + readingHelper->getPrevTotalCodePointCount(),
+            codePointCount - readingHelper->getPrevTotalCodePointCount(),
+            probability, &pos);
 }
 
 bool DynamicPatriciaTrieWritingHelper::addBigramWords(const int word0Pos, const int word1Pos,
@@ -97,4 +106,112 @@
     return false;
 }
 
+bool DynamicPatriciaTrieWritingHelper::markNodeAsMovedAndSetPosition(
+        const DynamicPatriciaTrieNodeReader *const originalNode, const int movedPos) {
+    int pos = originalNode->getNodePos();
+    const bool usesAdditionalBuffer = mBuffer->isInAdditionalBuffer(pos);
+    const uint8_t *const dictBuf = mBuffer->getBuffer(usesAdditionalBuffer);
+    if (usesAdditionalBuffer) {
+        pos -= mBuffer->getOriginalBufferSize();
+    }
+    // Read original flags
+    const PatriciaTrieReadingUtils::NodeFlags originalFlags =
+            PatriciaTrieReadingUtils::getFlagsAndAdvancePosition(dictBuf, &pos);
+    const PatriciaTrieReadingUtils::NodeFlags updatedFlags =
+            DynamicPatriciaTrieReadingUtils::updateAndGetFlags(originalFlags, true /* isMoved */,
+                    false /* isDeleted */);
+    int writingPos = originalNode->getNodePos();
+    // Update flags.
+    if (!DynamicPatriciaTrieWritingUtils::writeFlagsAndAdvancePosition(mBuffer, updatedFlags,
+            &writingPos)) {
+        return false;
+    }
+    // Update moved position, which is stored in the parent position field.
+    if (!DynamicPatriciaTrieWritingUtils::writeParentPositionAndAdvancePosition(
+            mBuffer, movedPos, &writingPos)) {
+        return false;
+    }
+    return true;
+}
+
+// Write new node at writingPos.
+bool DynamicPatriciaTrieWritingHelper::writeNodeToBuffer(const bool isBlacklisted,
+        const bool isNotAWord, const int parentPos, const int *const codePoints,
+        const int codePointCount, const int probability, const int childrenPos,
+        const int originalBigramListPos, const int originalShortcutListPos,
+        int *const writingPos) {
+    // Create node flags and write them.
+    const PatriciaTrieReadingUtils::NodeFlags nodeFlags =
+            PatriciaTrieReadingUtils::createAndGetFlags(isBlacklisted, isNotAWord,
+                    probability != NOT_A_PROBABILITY, originalShortcutListPos != NOT_A_DICT_POS,
+                    originalBigramListPos != NOT_A_DICT_POS, codePointCount > 1,
+                    3 /* childrenPositionFieldSize */);
+    if (!DynamicPatriciaTrieWritingUtils::writeFlagsAndAdvancePosition(mBuffer, nodeFlags,
+            writingPos)) {
+        return false;
+    }
+    // Write parent position
+    if (!DynamicPatriciaTrieWritingUtils::writeParentPositionAndAdvancePosition(mBuffer, parentPos,
+            writingPos)) {
+        return false;
+    }
+    // Write code points
+    if (!DynamicPatriciaTrieWritingUtils::writeCodePointsAndAdvancePosition(mBuffer, codePoints,
+            codePointCount, writingPos)) {
+        return false;;
+    }
+    // Write probability when the probability is a valid probability, which means this node is
+    // terminal.
+    if (probability != NOT_A_PROBABILITY) {
+        if (!DynamicPatriciaTrieWritingUtils::writeProbabilityAndAdvancePosition(mBuffer,
+                probability, writingPos)) {
+            return false;
+        }
+    }
+    // Write children position
+    if (!DynamicPatriciaTrieWritingUtils::writeChildrenPositionAndAdvancePosition(mBuffer,
+            childrenPos, writingPos)) {
+        return false;
+    }
+    // Copy shortcut list when the originalShortcutListPos is valid dictionary position.
+    if (originalShortcutListPos != NOT_A_DICT_POS) {
+        int fromPos = originalShortcutListPos;
+        mShortcutPolicy->copyAllShortcuts(&fromPos, writingPos);
+    }
+    // Copy bigram list when the originalBigramListPos is valid dictionary position.
+    if (originalBigramListPos != NOT_A_DICT_POS) {
+        int fromPos = originalBigramListPos;
+        if (!mBigramPolicy->copyAllBigrams(&fromPos, writingPos)) {
+            return false;
+        }
+    }
+    return true;
+}
+
+bool DynamicPatriciaTrieWritingHelper::createAndInsertNodeIntoPtNodeArray(const int parentPos,
+        const int *const nodeCodePoints, const int nodeCodePointCount, const int probability,
+        int *const forwardLinkFieldPos) {
+    const int newPtNodeArrayPos = mBuffer->getTailPosition();
+    if (!DynamicPatriciaTrieWritingUtils::writeForwardLinkPositionAndAdvancePosition(mBuffer,
+            newPtNodeArrayPos, forwardLinkFieldPos)) {
+        return false;
+    }
+    int writingPos = newPtNodeArrayPos;
+    if (!DynamicPatriciaTrieWritingUtils::writePtNodeArraySizeAndAdvancePosition(mBuffer,
+            1 /* arraySize */, &writingPos)) {
+        return false;
+    }
+    if (!writeNodeToBuffer(false /* isBlacklisted */, false /* isNotAWord */, parentPos,
+            nodeCodePoints, nodeCodePointCount, probability, NOT_A_DICT_POS /* childrenPos */,
+            NOT_A_DICT_POS /* originalBigramsPos */, NOT_A_DICT_POS /* originalShortcutPos */,
+            &writingPos)) {
+        return false;
+    }
+    if (!DynamicPatriciaTrieWritingUtils::writeForwardLinkPositionAndAdvancePosition(mBuffer,
+            NOT_A_DICT_POS /* forwardLinkPos */, &writingPos)) {
+        return false;
+    }
+    return true;
+}
+
 } // namespace latinime
diff --git a/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_writing_helper.h b/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_writing_helper.h
index f8165fc..524f361 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_writing_helper.h
+++ b/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_writing_helper.h
@@ -23,6 +23,7 @@
 
 class BufferWithExtendableBuffer;
 class DynamicBigramListPolicy;
+class DynamicPatriciaTrieNodeReader;
 class DynamicPatriciaTrieReadingHelper;
 class DynamicShortcutListPolicy;
 
@@ -51,6 +52,17 @@
     BufferWithExtendableBuffer *const mBuffer;
     DynamicBigramListPolicy *const mBigramPolicy;
     DynamicShortcutListPolicy *const mShortcutPolicy;
+
+    bool markNodeAsMovedAndSetPosition(const DynamicPatriciaTrieNodeReader *const nodeToUpdate,
+            const int movedPos);
+
+    bool writeNodeToBuffer(const bool isBlacklisted, const bool isNotAWord, const int parentPos,
+            const int *const codePoints, const int codePointCount, const int probability,
+            const int childrenPos, const int originalBigramListPos,
+            const int originalShortcutListPos, int *const writingPos);
+
+    bool createAndInsertNodeIntoPtNodeArray(const int parentPos, const int *const nodeCodePoints,
+            const int nodeCodePointCount, const int probability, int *const forwardLinkFieldPos);
 };
 } // namespace latinime
 #endif /* LATINIME_DYNAMIC_PATRICIA_TRIE_WRITING_HELPER_H */