If it's illegal for someone under 21 to drink, it should be illegal for them to drink and drive. That's a no-brainer.

如果不满21岁喝酒是违法的，那他们酒后驾车也应是违法的。这太容易理解了。

《柯林斯英汉双解大词典》

Exactly! Here is another example. Some people don't like to buckle their seatbelt in the car, but to me, that's a no brainer.

是啊，坐车系安全带，这是一定要的埃就跟在户外要防晒一样。没什么可说的。

youdao

Yeah, I think that mandatory voting is a no-brainer. It's a dumb idea. It's a terrible idea.

我认为强制投票这事不用多考虑，是一个极其愚蠢，极其糟糕的想法。

对于义务投票制 - SpeakingMax英语口语达人

That's a no-brainer, like placing Tiger Woods on a Wheaties box.

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"When you have the pleasure of working with the No. 1 athlete in the world, that's a no-brainer, " said Glance, who won gold as part of the U.S. 4x100-meter relay team at the Montreal Games in 1976.

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"That's a no-brainer, " says Rosenbaum.

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