From an evolutionary point of view, panic can be a useful thing in moments of great danger.

从进化论的观点来看，在非常危险的时刻出现恐慌是件好事。

youdao

So let's take a look then at somewhere where this is actually a useful thing to know so this is compare1.c.

那么再然我们看一看,一些有用的东西,这是compare1。

youdao

In a university, a European and a one-eyed man walked along a one-way road with a useful thing. This is a usual thing.

在一所大学里，一个欧洲人和一个独眼龙拿着一件有用的工具沿着一条单行道走着。这是一件平常事。

youdao

So again, if you do a calculation where you're close enough to the ideal gas and you need to design your, if you have an engineer designing something that's got a bunch of gases around, this is a useful thing to use.

要研究近似理想气体的表现时,这个方程非常有用,下面再来看一个，对我们来说最有意思的,实际气体状态方程：,范德瓦尔斯方程。

麻省理工公开课 - 热力学与动力学课程节选

And this is actually a useful thing to know.

这是一个很有用的理论，大家都应该记住。

耶鲁公开课 - 心理学导论课程节选

So let's take a look then at somewhere where this is actually a useful thing to know so this is compare1.c. So, in compare1.c I've stripped out the comments in my version but in your version you do have comments for reference and it's actually pretty self-explanatory if you just read through the code.

那么再然我们看一看,一些有用的东西,这是compare1。c，所以在compare1。c中，在我的版本中,我吧注释去掉了,但是在你们的版本中是有注释的,这是相当容易理解的,如果你通读这段代码。

哈佛公开课 - 计算机科学课程节选

This may or may not prove a useful thing to know on certain Saturday nights.

NEWYORKER: The Disconnect

So the President feels very strongly that this was a useful thing to do.

WHITEHOUSE: Press Briefing

Sort of a lazy man's social phone, but we reckon that can be quite a useful thing for the targeted demographic of college students.

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