monkey business
US /ˈmʌŋ.ki ˈbɪz.nɪs/
UK /ˈmʌŋ.ki ˈbɪz.nɪs/

1.
鬼把戏, 胡闹, 不正当行为
silly, dishonest, or mischievous behavior
:
•
Stop all that monkey business and get to work!
别再搞那些鬼把戏了,快去工作!
•
The teacher suspected some monkey business was going on during the exam.
老师怀疑考试期间有人搞鬼把戏。