how old is the oldest
how old be the old
pro:int adj aux det:art adj
how old is the oldest ?
h aʊ WORD_BOUNDARY oʊ l d WORD_BOUNDARY ɪ z WORD_BOUNDARY ð ɪ WORD_BOUNDARY oʊ l d ɪ s t WORD_BOUNDARY
h o w WORD_BOUNDARY o l d WORD_BOUNDARY i s WORD_BOUNDARY t h e WORD_BOUNDARY o l d e s t WORD_BOUNDARY