idle

他知道该做什么，他就是极其懒惰。

He knows what has to be done, he's just bone ___idle.

我必须承认，我年轻时有时很懒惰。

I must admit I was sometimes ___idle when I was younger.

午休期间，工厂的机器闲置着。

During the lunch break, the factory machinery sat ___idle.