de ce s+au învechit
de ce s au învechit ?
d e WORD_BOUNDARY t̠ʃ e WORD_BOUNDARY s e WORD_BOUNDARY aʊ WORD_BOUNDARY ɨ n v e k i t WORD_BOUNDARY
d e WORD_BOUNDARY c e WORD_BOUNDARY s WORD_BOUNDARY a u WORD_BOUNDARY î n v e c h i t WORD_BOUNDARY