Guess, guard, tongue Silent 'u'
Sighn, resign, foreign Silent 'g'
Knock, know, knee Silent 'k'
Wrist, wrote, wrong Silent 'w'
Thumb, doubt, plumber Silent 'b'
Autumn, damn, column. Silent 'n'
Half, calm, talk Silent 'l'
Hour, ghost, honest Silent 'h'
Listen, mortgage, watch Silent 't'