he+eh he he he he
he eh he he he he .
h ɛ WORD_BOUNDARY  ɛ h WORD_BOUNDARY h ɛ WORD_BOUNDARY h ɛ WORD_BOUNDARY h ɛ WORD_BOUNDARY h ɛ WORD_BOUNDARY
h e WORD_BOUNDARY e h WORD_BOUNDARY h e WORD_BOUNDARY h e WORD_BOUNDARY h e WORD_BOUNDARY h e WORD_BOUNDARY