He's just smiling.

他只是微笑。

youdao

Then, as you get more comfortable maintaining eye contact, try saying hello or just smiling at them (not weirdly, just a regular smile as if to yourself).

然后，当你觉得渐渐适应了眼神交流之后，试着向对方打招呼，或者保持微笑（不是傻笑，而是发自内心的正常的微笑）。

youdao

You never know how many lives you can touch and change by just smiling.

你永远不知道你能用笑容打动甚至改变多少人的人生。

youdao

And it was a remarkable reaction of just patting us on the back, smiling and ushering us up to the front so that we could see it."

VOA: standard.2010.07.26

Professor Paul Bloom: I don't know if that's--The question is, "Is there a difference between smiling with your teeth versus just your lips closed?"

我不知道是否，问题是，微笑露齿与不露齿有不同吗“

耶鲁公开课 - 心理学导论课程节选

She just kept smiling.

NEWYORKER: Swimming

My overall feeling is that we are just not consistently conscious of smiling and the benefits it brings to ourselves and others, otherwise we would do it more often.

FORBES: New Data on Smiling

This person just did the online equivalent of smiling politely, excusing herself to go to the bathroom and leaving you alone at the bar.

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