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使人扫兴的人；大煞风景的人
If you call someone a killjoy, you are critical of them because they stop other people from enjoying themselves, often by reminding them of something unpleasant.
例句
Don't be such a killjoy!...
别那么扫兴！
This is a classic example of the killjoy attitudes of officialdom.
这是那种典型的令人不快的官僚主义态度。