for half an hour
for half a hour
prep n det:art n
for half an hour .
f ɔː ɹ WORD_BOUNDARY h æ f WORD_BOUNDARY ɐ n WORD_BOUNDARY aʊ ɚ WORD_BOUNDARY
f o r WORD_BOUNDARY h a l f WORD_BOUNDARY a n WORD_BOUNDARY h o u r WORD_BOUNDARY