have someone by the balls
US /hæv ˈsʌmˌwʌn baɪ ðə bɔlz/
UK /hæv ˈsʌmˌwʌn baɪ ðə bɔlz/

1.
完全控制住某人, 拿捏住某人
(vulgar slang) to have complete control over someone, especially by having information that could harm them
:
•
The prosecutor really had him by the balls with all the evidence.
检察官掌握所有证据,完全控制住他了。
•
If you owe them money, they'll have you by the balls.
如果你欠他们钱,他们就会拿捏住你。