On average, students have to spend 3 hours finishing homework every day, but if we are stuck by difficult questions, the time will be extended.

学生平均每天要花三个小时来完成作业，但是如果遇到难题，完成作业的时间就得延长。

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According to a study by Australian National University, Australian children and Chinese children have the same level of eyesight before they start school, but once they enter primary school, Chinese children only spend about an hour a day outside, while Australian children spend three to four hours each day in the sunshine.

澳大利亚国立大学的一项研究显示，澳大利亚的孩子和中国的孩子在入学前的视力水平相同。但是一旦他们进入小学，中国的孩子每天只会在户外度过一个小时，而澳大利亚的孩子每天在阳光下待三到四个小时。

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Trying to achieve full coverage is often a waste of time; if you have to spend hours trying to force tests to exercise error conditions and exceptional cases, you get diminishing returns.

试图实现完全承保常常是浪费时间，如果您花上几个小时去测试错误情况和异常情况，您的受益会减少。

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We can spend late hours rendering something and then have a go-by in thirty seconds.

我们可以用后来的时间,对一些东西做艺术处理,然后跳过这三十秒。

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Anyone who is going, will probably have to spend hours outside while the ceremonies take place.

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The crew will have to spend hours out of their day to avoid the physical problems of microgravity.

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Dealers don't have to spend hours haggling their way to a profit, and they can turn over inventory faster.

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