on n' ouvre pas
on ne ouvrir pas
pro:sub neg v neg
on n' ouvre pas .
ɔ̃ WORD_BOUNDARY  ɛ n WORD_BOUNDARY u v ʁ WORD_BOUNDARY p a WORD_BOUNDARY
o n WORD_BOUNDARY n ' WORD_BOUNDARY o u v r e WORD_BOUNDARY p a s WORD_BOUNDARY