The weather is cold enough to freeze the balls of a brass monkey.
天气真的是太冷啦！

ball up
弄糊涂

Ball of fire = a very enthusiastic and ambitious person热情，有志向的人
Day is a real ball of fire when it comes to writing scripts!
Day写脚本的时候，真是充满热情。

drop the ball =搞砸
He dropped the ball at the meeting！
他搞砸了这个会议。

the old ball and chain =（爱管事的）老伴
I cant go out for dinner tonight the old ball and chain is making me stay home.
我晚上不能去吃饭了，我家的管家婆让我呆在家。

have a ball = 尽情享乐
I had a ball yesterday at the party.
我昨天在那个聚会上玩的很尽兴.