You must let go of the idea that to be single is to be unhappy and unfulfilled.

你必须放弃单身就不快乐不满足的想法。

《柯林斯英汉双解大词典》

Tutu seemed to be unhappy.

图图看起来并不高兴。

youdao

Those spending 10-19 hours per week on their devices were 41 percent more likely to be unhappy than lower-frequency users.

那些每周花10到19个小时在电子设备上的人与使用频率较低的人相比，不快乐的可能性高41%。

youdao

She would use this comment when advice seekers seemed to be denying situations that made them unhappy or uncomfortable.

VOA: special.2011.04.24

what do they have to be unhappy about?

他们有什么可不快乐的？

哈佛公开课 - 幸福课课程节选

Would you be happy or would you be unhappy, to discover that you actually have been living ? a life on the experience machine?

你会开心还是不开心，如果你发现实际上,你一直都是在体验机器里生活？

耶鲁公开课 - 死亡课程节选

The bottom line, if you are looking for an excuse to be unhappy you will surely find it.

FORBES: Readers Say

And if they do have kids, they are more likely to be unhappy about it.

FORBES: Careers And Marriage

Regardless of how they rule, a large portion of the country is sure to be unhappy.

ECONOMIST: Mexico's elections