"What's up?" I said to him.—"Just tired," he answered.

“出了什么事？”我对他说。— “只是累了，”他答道。

《柯林斯英汉双解大词典》

Are you pregnant, or just tired?

你是怀孕了，还是累了？

youdao

Just tired? Get more sleep.

如果仅仅是累了，就补充些睡眠。

youdao

I was just tired and had nothing else to do.

VOA: special.2010.08.01

It's just war is being dissed by those people that are just so tired of the killing.

这只是表明厌倦了杀戮的人们对战争的仇视

耶鲁公开课 - 欧洲文明课程节选

not just have the kids let them watch television because you're tired,

不能因为累，就一味地让孩子自己去看电视，

重要的是家庭教育 - SpeakingMax英语口语达人

Complexity is frustrating and too hard for persons tired from working all day (or just tired of working).

FORBES: Bungie's 'Destiny' Pushes Brand Beyond 'Halo'

She said no, she was just tired of giving in.

FORBES: Martin Luther King Day

They are just tired of being hectored by scientists proclaiming certain apocalypses that never pan out: Examples include acid rain and the death of the forest, asteroids, the population bomb, and a catastrophic extinction of species that has eluded detection.

FORBES: Sound, Fury And The Policy Of Climate Change