fighting fires Mum
fight fire Mum
part n n:prop
fighting fires mum.
f aɪ tʰ ɪ ŋ WORD_BOUNDARY f aɪ ə z WORD_BOUNDARY m ʌ m WORD_BOUNDARY
f i g h t i n g WORD_BOUNDARY f i r e s WORD_BOUNDARY m u m . WORD_BOUNDARY