1. Beat a dead horse

鞭打死马令其奔驰（徒劳）

I don't want to beat a dead horse. = I don't want to repeat something over and over again.

我不想重复的说一件事。

例子：I hate to beat a dead horse, but it is very important that you understand this before you leave.

我不想多此一举。但你离开以前必须了解这个。

2. Beaten by the ugly stick

被丑杖打过（生的难看）

She was beaten by the ugly stick. = She is very ugly.

她生的很难看。

例子：Did you see that dog? It looked like someone beaten by the ugly stick.

瞧见哪知狗没有？ 真难看，看来像被丑杖打过。

3. Beggars can't be choosers

讨饭的谈不上挑三拣四。

I know that beggars can't be choosers. = I know that if I am desperate I cannot be selective.

我知道在我走投无路的时候，我不能嫌好道歹。

例子：I didn't want to eat at this restaurant, but it is the only place that is open this late at night. I suppose that beggars can't be choosers.

我不想光顾这家饭店，但这么晚，别家都关门了。这时候我不嫌好道歹。