diff --git a/src/regexp_bt.c b/src/regexp_bt.c
index 70eab25..afea5e4 100644
--- a/src/regexp_bt.c
+++ b/src/regexp_bt.c
@@ -4764,7 +4764,7 @@
 
 /*
  * Match a regexp against a string ("line" points to the string) or multiple
- * lines ("line" is NULL, use reg_getline()).
+ * lines (if "line" is NULL, use reg_getline()).
  * Returns 0 for failure, number of lines contained in the match otherwise.
  */
     static long