Sometimes they had nothing to do in the office and just sat twiddling their thumbs.

有时候办公室里无事可做，他们就坐着无聊地打发时间。

youdao

Otherwise you will get wasted resources, people twiddling their thumbs or maybe doing work without approval.

否则你就是在浪费资源，人们无所事事或者就是在没有批准交付物的情况下工作。

youdao

Why should I be left alone holding the baby while all the boys are sitting around and twiddling their thumbs?

为什么这些苦差事使得我一个人干而男孩子们却懒洋洋地坐在那儿，闲得没事干？

youdao

"There simply aren't that many Army-trained doctors sitting twiddling their thumbs, " he added.

BBC: Health trust considers Army medics to staff Pontefract A&E

When there is no competition for the labour as there are vast armies of it sitting around twiddling their thumbs and looking for something to do.

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