What are you looking so smug about?

你怎么这样一副神气活现的样子？

《牛津词典》

Those baby-faced people now have another reason to be smug: a new Danish study says looking young apparently means a longer life.

那些长着娃娃脸的人现在又多了一个可以自鸣得意的理由了，因为一份来自丹麦的研究称，人显小很明显就会活得更长。

youdao

There were the demands I had made miraculously granted, looking a bit smug.

ECONOMIST: Travelling through life first class

The good news for Democrats is that Obama delivered the goods without looking too snippy or smug.

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