I don't know what has happened
I do know what have happen
pro:sub mod v pro:int aux part
i don't know what has happened.
aɪ WORD_BOUNDARY d əʊ n tʰ WORD_BOUNDARY n əʊ WORD_BOUNDARY w ɒ tʰ WORD_BOUNDARY h ɐ z WORD_BOUNDARY h æ pʰ ə n d WORD_BOUNDARY
i WORD_BOUNDARY d o n ' t WORD_BOUNDARY k n o w WORD_BOUNDARY w h a t WORD_BOUNDARY h a s WORD_BOUNDARY h a p p e n e d . WORD_BOUNDARY