You criticize my appearance, and then you stab me in the back!

你批评我的外表，然后在背后捅我一刀！

youdao

Such a vicious lie could be nothing but a stab in the back.

这样一种恶毒的谎言简直是暗箭伤人。

《新英汉大辞典》

"Passive aggressive people will say yes to your face and stab you in the back," she says.

她说：“消极对抗型的人当面同意你的观点，却可能在背后给你一刀。”

youdao

This would surely be a stab in the back.

VOA: special.2010.01.24

First of all, I found secretary Rumsfeld a very easy person to deal with in a sense that he's very professional, very strict, very honest, not the kind of guy who, you know, take a different position, try to around behind your back. If he's going to stab you, he's going to stab you in the chest.

首先，我发现拉姆斯菲尔德秘书长,是很容易打交道的人,我指的是他非常专业，非常严格，非常诚恳，不像那类人，因为观点立场不同,就从你背后放冷箭,如果他想杀了你，也是从正面进攻。

普林斯顿公开课 - 国际座谈会课程节选

"The President thought it was a major stab in the back, " says a White House adviser.

CNN: Fasten your seat belts

He said staff had coped with new working practices, shifts and the demands of a digital project and the job cuts were a "stab in the back".

BBC: Trinity Mirror job cuts: Newspapers could go says union

Another stab in the back came from his Nationalist Action partners in the coalition, who called for elections to be held on November 3rd, nearly 18 months ahead of schedule.

ECONOMIST: Turkey's reforms