dog-tired 筋疲力尽的，疲倦极了的，累得动弹不得的

This morning my coach made me run five miles in the summer heat. I'm so dog-tired now I can't even walk.

今天上午我的教练要我在炎炎夏日下长跑五英里。现在我已经累成了狗，路都走不动了。

dusk 黄昏，傍晚，暮色

By dusk we were dog-tired and heading for home.

到黄昏时，我们累得像狗一样地回家了。