谢谢你邀请我，不过我实在是太累了。

Thank you very much for asking me, but I feel rather tired.

youdao

我强烈建议我们的老板再招一个人，我实在是太累了。

I strongly advised my boss to hire a "spare-tire", because I am so tired.

youdao

也许我的心脏年纪大了，开始衰弱；又或者我实在是太累了。

Maybe my heart is getting old and weak, or maybe I'm just dog-tired.

youdao

I'm so tired that my knees are shaking.

我实在是太累了，我的膝盖都在发颤了。

so that 实战 - SpeakingMax英语口语达人