We need to let the money out by spending on useful and necessary things.

我们应该把钱花出去，花在有意义的事情上，蓄水没有意义，除非我们用它来发电；

youdao

Not really. I can live without it. It just makes people's life colorful. It is not so useful and necessary like microwave ovens.

并不是很重要，没有新发明我也可以过得很好。新发明只是使人们生活更多姿多彩，而并非非常有用和必要的，比如说微波炉。

youdao

Nevertheless, ancient DNA can undoubtedly be a useful and necessary tool to unveil the mysterious migration history of human beings.

但是毫无疑问，古代dna研究是揭开人类历史神秘面纱非常有用且必不可少的工具。

youdao

They are seen by HQ as useful and necessary, but also as too close to the issue, too soft on the Chinese, to be fully trusted.

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AdverseEvents "is useful and necessary, but it may not be sufficient, given the problems with the FDA data, " say Joe Graedon, a pharmacologist who runs ThePeople'sPharmacy.com, a website where visitors often discuss their own experiences with drugs.

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Arrogance, in this case, is a necessary and useful quality.

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