at the mercy of 完全有……支配，任由……摆布
I'm not going to put myself at the mercy of the bank.
We were at the mercy of the enemy.
A:Why are you still here? You are supposed to be in the cram school now?
B:Because I think it's more meaningful to read some books at home. Come on, this is my life, I don't wanna put myself at the mercy of others.
Jacob Latimore、Issa——like 'Em All