diff --git a/epub_examples.py b/epub_examples.py
index cf2d193..ed1f266 100644
--- a/epub_examples.py
+++ b/epub_examples.py
@@ -448,6 +448,10 @@ def _try_strip_prefix(token: str, nikkud_index: dict) -> list[tuple[str, str, st
     return results
 
 
+# Public alias for use by sentence_difficulty module
+try_strip_prefix = _try_strip_prefix
+
+
 def _build_nikkud_index(words: dict) -> dict[str, list[tuple[str, str]]]:
     """Build a mapping from nikkud form to list of (unique_key, match_type).