beg off

动词 beg off:

1. ask for permission to be released from an engagement
   同义词：excuse

1. He promised to go with us, but he has since begged off.
   他本来答应跟我们同往，但后来一直借故推辞了。
2. Father told Tom to rake the yard, but Tom tried to beg off.
   父亲要求汤姆清扫庭院，但他却要求放了他。