dead beat 无差拍；非周期的；筋疲力尽的；疲倦已极；惨败；疲惫不堪

【例句】
You've been working too hard, you look dead beat.
你工作太努力了，你看上去已经筋疲力尽了。

I have done my work all night and I have been dead beat already!
我熬夜工作了，已经筋疲力尽了。