Now,he thinks short is better. "I've gotten researchers telling me that you don't realize is how long someone can have a high level of concentration.

VOA: standard.2010.03.26

But I don't really know about how long it would take people to hack, like, the general firewall

但我不知道人们具体要用多长时间才能穿过防火墙，

理想是当密码专家 - SpeakingMax英语口语达人

If we weren't so pressed for time, I kinda wanna see how long we could get away with this before it gets awkward, but that, in fact, is an infinite loop t hat's hopefully deliberate.

如果有时间，我想看看,我们需要花多长时间解决这一问题，事实上，它是我故意,使用的无穷循环。

哈佛公开课 - 计算机科学课程节选

"A lot of people don't know how long to cook salmon, " Ms. Erickson said.

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There were times when even the Heat themselves didn't know how long the streak was.

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No reason was given, and it isn't clear how long the ban will be enforced.

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