Once is more than enough. How can you do it again?

一之为甚， 其可再乎?

《新英汉大辞典》

Down-down: it's impossible! Even the strongest warrior, William, cannot move it? How can you do it?

当当：这怎么可能！连力气最大的威廉都搬不动你怎么可能搬的开呢？

youdao

Can you show me how to do it?

你能教我怎么做吗？

《牛津词典》

She taught me how to climb. Come on, Forrest,you can do it.

VOA: standard.other

Like how can you possibly figure that out with actually compelling a machine to do it for you and sure enough we chatted for a few moments, I kind of gently pointed out well it's kind of like problem 7 last year.

就好像去逼计算机为你做这件事,就能解决问题一样,我们确实谈过这个问题，我委婉地告诉他,这种情况与我们去年讲过问题7类似。

哈佛公开课 - 计算机科学课程节选

If you know how to do it, you can get it for really cheap.

要是你知道怎么做的话，你就可以买到很便宜的票。

实惠的歌舞剧 - SpeakingMax英语口语达人

But how can you do it without spending, cutting jobs, or installing some new, fancy technology?

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"In your last seven months, you can make peace in Sudan, and this is how you can do it, " he said.

CNN: 18 students arrested in Darfur protest at White House

You want to get across the quantitative benefits of your plan and the results you can provide without explaining exactly how you will do it, which is your intellectual property.

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