我决不可能做那样的事。你一定是在开玩笑吧！

No way am I doing that. You must be joking!

《牛津词典》

汤姆说他打算卖掉他的商店去上医学院，他一定是在开玩笑。

Tom must be joking when he said he plans to sell his shop and go to medical school.

youdao

你一定是在开玩笑！我不能住这儿！

You've got to be kidding! I can't live here!

《柯林斯英汉双解大词典》