rap somebody on the knuckles

US /ræp ˈsʌm.bɑː.di ɑːn ðə ˈnʌk.əlz/
UK /ræp ˈsʌm.bɑː.di ɑːn ðə ˈnʌk.əlz/
"rap somebody on the knuckles" picture
1.

厳しく叱責する, お灸をすえる

to criticize someone for something they have done wrong

:
The teacher had to rap the student on the knuckles for cheating on the exam.
教師は試験でカンニングした生徒を厳しく叱責しなければならなかった。
The manager rapped him on the knuckles for being late to the meeting again.
マネージャーは彼がまた会議に遅刻したことで彼を叱責した