slap on the back 拍拍背
slap a label on 贴上标签
slap someone's face 扇某人耳光
A: Why did you slap him?
A：你为什么要打他的耳光？
B: I was very angry at his behavior.
B：我对他的行为感到非常愤怒。
1) 扇耳光
2) 拍打
3) 快速地贴上或盖上
1. 扇耳光；拍打
verb
1. to hit someone or something with the palm of the hand