"落井下石"用英语怎么说?

“落井下石”,汉语成语意思是看见人要掉进陷阱里,不伸手救他,反而又扔下石头(drop stones on somebody who has fallen into a well);比喻乘人有危难时加以陷害。与英语习语“kick/hit/strike a person when he is down”意思相近。

例句

我终是无法做到在吉米倒霉时落井下石。

In the end I just couldn't kick Jimmy when he was down.