拧紧

zhè ge gōng jù shì nǐng jǐn luó sī de

这个工具是拧紧螺丝的。

This tool is for tightening screws.

jiǎn chá yī xia luó sī dīng shì fǒu nǐng jǐn le

检查一下螺丝钉是否拧紧了。

Check that the screws are tight.