You have too much time on your hands. Why don't you start a hobby?

你有太多的空闲时间，何不开始一样嗜好呢？

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If you have a lot of time on your hands, you can walk the Freedom Trail.

如果您时间充裕的话，可以走一趟自由之路。

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When you get some time on your hands, look for the word in your dictionary and write it down.

在你有时间时，在字典里查阅这些单词并把他们写下来。

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So, I encourage you to do that the next time you have some free time on your hands, maybe at IAP or some time like that.

下次你有空余时间时,我鼓励你去看一看，也许在IAP或者什么时候。

麻省理工公开课 - 化学原理课程节选

But then when you reach 70, you have far too much time on your hands.

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You might find a better use for the extra time on your hands.

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If you are constantly checking your e-mail, this could mean you have too much free time on your hands and need to work on other tasks.

FORBES: 12 Tips For Increasing Productivity