He offered to tighten up the lug nuts for her, but instead he secretly loosened them.

他提出要为她拧紧螺母，但他却偷偷松开了它们。

The employees took off lug nuts with an air wrench, hoisted off the car's 50-pound tire, swapped in a new tire and got the lug nuts back on.

员工们用气动扳手取下轮胎螺母，然后把50磅重的轮胎卸下，换上一个新轮胎，最后把螺母装回去。