stab sb in the back 在某人背后捅一刀, 背叛某人

今天和大家分享的是：
stab sb in the back  在某人背后捅一刀, 背叛某人
A: I wouldn't trust John if I were you.
B: I don't. The last time I did, he stabbed me in theback.
(A: 我若是你，就不会相信约翰。)
(B: 我才不信他呢。上次我信他，结果他在我背后捅一刀。)