He has become a convenient whipping boy for the failures of the old regime.

他成了承担旧政权失败的现成的替罪羊。

《柯林斯英汉双解大词典》

He worked the whipping-boy mine to ever-increasing profit.

他把那代鞭的男孩当做一个矿山开采，得到的好处越来越大了。

youdao

I knew that if I didn't stand up to him, I would become his new whipping boy - so I turned around and with all my might, made a fist and hit him square in the jaw.

我知道如果我不敢面对他，我将成为又一个被他欺负的倒霉鬼，于是我转过身，用尽所有的力量，一拳打在他的下巴上。

youdao

The atmosphere in Congress was tense before Thanksgiving, he said, adding that he feels "automakers have become the whipping boy" for the industry bailout.

CNN: Automaker execs say they'll accept $1 pay

The current fashionable whipping boy is, of course, the Suhartos.

CNN: CONTEMPLATING THE DYNASTY BEYOND 2000

Another whipping-boy is the European Union (EU).

ECONOMIST: Tussles in a flat landscape