he he he em em
he he he em em .
h ɛ WORD_BOUNDARY h ɛ WORD_BOUNDARY h ɛ WORD_BOUNDARY  ɛ m WORD_BOUNDARY ɛ m WORD_BOUNDARY
h e WORD_BOUNDARY h e WORD_BOUNDARY h e WORD_BOUNDARY e m WORD_BOUNDARY e m WORD_BOUNDARY