beg off   (TTS發音)

ask to be excused； ask that sb. may be excused or forgiven懇求免除懲罰或責任；為某人求情

    He promised to go with us，but he has since begged off. 他本來答應跟我們同往，但此後卻借故推辭了。

    The Headmaster means to punish him， but my father is going to try to beg him off. 校長打算處罰他，但我父親將竭力懇求免除對他處分。