I don't know how come
I do know how come
pro:sub mod v pro:rel v
i don't know how come.
aɪ WORD_BOUNDARY d oʊ n t WORD_BOUNDARY n oʊ WORD_BOUNDARY h aʊ WORD_BOUNDARY k ʌ m WORD_BOUNDARY
i WORD_BOUNDARY d o n ' t WORD_BOUNDARY k n o w WORD_BOUNDARY h o w WORD_BOUNDARY c o m e . WORD_BOUNDARY