Sure ..Bradley ... when hell freezes over!

好啊，布兰得利，等太阳从西边出来的那天吧。

Or Sure, I'll call him ... when hell freezes over!

或者是，“当然，我绝不会再给他打电话。”

Madeline stares at him with her cold, green eyes and says, " That will happen when hell freezes over."

玛德琳用她那清冷的碧眸凝视着他，说道：“除非地狱结冰（那绝不可能）。”

For example, if something is never going to happen, like not a chance, I can say " when hell freezes over" .

比如，如果某件事情永远不会发生，也就是可能性为0，那么我可以说" when hell freezes over" 。

I'll believe his promises when hell freezes over.

当地狱结冰时，我会相信他的诺言。

It will be a cold day in hell and when hell freezes over also mean the same thing: there is no chance that something will happen.

It will be a cold day in hell和when hell freezes over也意味着同样的意思，即绝不会发生某事。

“I'll join you when hell freezes over, ” said Neville. “Dumbledore's Army! ” he shouted, and there was an answering cheer from the crowd, whom Voldemort's Silencing Charms seemed unable to hold.

“除非地狱结冰我才会跟你走。”纳威说，“邓布利多军！”他大喊一声，人群里立刻响起激昂的回应，对此伏地魔无声无息咒似乎也不起作用了。