Theory is nice, but practice is better.

理论不如实践好。

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Note that this technique can take a while to perfect, but practice makes perfect.

这个技巧需要练习，熟能生巧。

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This is certainly a theoretical risk but in practice there is seldom a problem.

这在理论上肯定有风险，但在实践中却很少出问题。

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But that idea failed. So the agency decided to use the plane for what was then a new practice: smokejumping.

VOA: special.2009.11.24

But practice this, because it's something that's such an easy way to ask such a variety of questions.

但是你仍然需要好好练习，因为这个简单的用法能够提出各种各样的问题。

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No, no. But if you have a UROP, or you have a sports practice or something, we will allow that.

不行，但是如果你得到本科生研究计划，或者你要进行体育锻炼，我们是能够接受的。

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But practice sessions are one thing.

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But the practice is based not on the brainchild of any university professor or crime expert, but in fiction - the character of Sherlock Holmes, created by Sir Arthur Conan Doyle.

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Economic analysis is itself value-free, but in practice it encourages a cosmopolitan interest in natural equality.

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