we don't open it
we do open it
pro:sub mod v pro:per
we don't open it.
w iː WORD_BOUNDARY d əʊ n tʰ WORD_BOUNDARY əʊ pʰ ə n WORD_BOUNDARY ɪ tʰ WORD_BOUNDARY
w e WORD_BOUNDARY d o n ' t WORD_BOUNDARY o p e n WORD_BOUNDARY i t . WORD_BOUNDARY