It's out of the question!

Idiom: out of the question

Definition:

Not possible

Examples:

1) “You can’t retake the test.  That’s out of the question!”

2) That’s out of the question that I’ll eat that!

中文解释：http://www.youzienglish.com/main/idiom_of_the_day/out_of_the_question/cn/