fängt 's an zu pfeifen
fängt 's an zu pfeifen .
f ɛ ŋ t WORD_BOUNDARY  ɛ s WORD_BOUNDARY  a n WORD_BOUNDARY ts uː WORD_BOUNDARY pf aɪ f ə n WORD_BOUNDARY
f ä n g t WORD_BOUNDARY ' s WORD_BOUNDARY a n WORD_BOUNDARY z u WORD_BOUNDARY p f e i f e n WORD_BOUNDARY