People blow on their hands to keep their hands warm.

人们在手上吹气来让手暖和。

youdao

They now have yet another drug problem on their hands.

他们现在又在处理另一个与毒品有关的问题。

《柯林斯英汉双解大词典》

A few turned somersaults, others walked on their hands with their feet in the air.

一些人在翻筋斗，另一些人则是倒立把脚竖到空中，用手走路。

youdao

But the truth is they might already have on their hands the blood of some young soldier or that of an Afghan family."

VOA: special.2010.07.31

They would get lesions on their hands, for example, the part of their body that was really in close contact with the cows.

比如,在与奶牛亲密接触的身体部位,也就是手上 也许会出斑

耶鲁公开课 - 生物医学工程探索课程节选

So, all that talking on the bus, and the way they're moving their hands, the bug, that's all where this language is rising from.

因此，那些公交车上的谈话，和他们的手舞足蹈，他们的疯狂，都是语言的来源。

耶鲁公开课 - 1945年后的美国小说课程节选

Conspirators who push the whole Obama birther thing similarly have too much time on their hands.

FORBES: More Questions Of Koch Brothers' Fingers In Scott Walker's Wisconsin Pie As 'Jason' Identity Revealed?

They had time on their hands and a certain anti-corporate attitude, amplified by their surprise unemployment.

FORBES: Age of Context: Social Media Becomes a Mature Platform

As the baby-boom generation retires in ever-increasing numbers, more people will have leisure-time on their hands.

CNN: Looking to the classroom to open doors, enrich the soul