knob

n. 把手,瘤

You may turn the right knob on the TV to switch it on.

你可以拧电视上右边的旋钮把它打开。

`Does this knob come off?' `No, it's fixed on permanently.'

｀这个把手能拆下来吗?＇｀不能, 那是固定的.＇