upset本身作形容词。
upsetadj.难过；不高兴；失望；沮丧；肠胃不适；腹泻；
v.使烦恼；使心烦意乱
We risk upsetting the ecological balance of the area.
我们有可能破坏这个地区的生态平衡。
Why did you have to go and upset your mother like that?
你干吗非得让你母亲那样伤心呢？
Naturally, I get upset when things go wrong.
事情出了错，我当然就会很烦。
