what have they been doing
what have they be do
pro:int v pro:sub aux part
what have they been doing ?
w ɒ t WORD_BOUNDARY h a v WORD_BOUNDARY ð eɪ WORD_BOUNDARY b iː n WORD_BOUNDARY d uː ɪ ŋ WORD_BOUNDARY
w h a t WORD_BOUNDARY h a v e WORD_BOUNDARY t h e y WORD_BOUNDARY b e e n WORD_BOUNDARY d o i n g WORD_BOUNDARY