I couldn't understand you
I could understand you
pro:sub mod v pro:per
i couldn't understand you.
aɪ WORD_BOUNDARY k ʊ d ə n t WORD_BOUNDARY ʌ n d ə ɹ s t æ n d WORD_BOUNDARY j uː WORD_BOUNDARY
i WORD_BOUNDARY c o u l d n ' t WORD_BOUNDARY u n d e r s t a n d WORD_BOUNDARY y o u . WORD_BOUNDARY