I am not sure
I be not sure
pro:sub cop neg adj
i am not sure.
aɪ WORD_BOUNDARY æ m WORD_BOUNDARY n ɑ t WORD_BOUNDARY ʃ ʊ ɹ WORD_BOUNDARY
i WORD_BOUNDARY a m WORD_BOUNDARY n o t WORD_BOUNDARY s u r e . WORD_BOUNDARY