I'm not too sure
I not too sure
pro:sub neg adv adj
i'm not too sure .
aɪ m WORD_BOUNDARY n ɑː t WORD_BOUNDARY t uː WORD_BOUNDARY ʃ ʊ ɹ WORD_BOUNDARY
i ' m WORD_BOUNDARY n o t WORD_BOUNDARY t o o WORD_BOUNDARY s u r e WORD_BOUNDARY