tighten

Use a wrench to tighten the loose bolt on the bicycle frame so it doesn't rattle.

(Chinese) 使用扳手拧紧自行车架上松动的螺栓，使其不再发出嘎嘎声。

The safety rules were revised to tighten control over the handling of hazardous chemicals.

(Chinese) 安全规则经过修订，以加强对危险化学品处理的控制。