All the time these two factors affect each other, that is why smiling when sad makes you happier and it is why you laugh when you find something funny.

这两项因素一直都是互相影响的，这就是为什么难受的时候微笑会使你开心些，同样也说明了为什么当发现有趣的事情时你会大笑。

youdao

When was the last time you were angry or sad?

你上一次生气或者悲伤是什么时候？

youdao

I've also felt sad some time, but when I think of you, I will regard those "sad matters" as nothing to feel sad about.

我也有悲痛过，然而一想起你的事情，我就觉得我的那些所谓“痛苦”，其实是庸人自扰。

youdao

It's going to be sad when I have to leave but there comes a time where you say no, enough is enough.

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So this is a very sad time when a plant closes that's been the cornerstone of your community for, you know, most of the century.

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