It is such thin ice that we can't skate ______.应该填on还是on it?

问题描述:

It is such thin ice that we can't skate ______.应该填on还是on it?

填on,因为在从句中,that这个引导词就是指ice
相当于:we can't skate on that(the ice)

It is such thin ice that we can't skate on.

on it

on

on 这是一个从句修饰ice,不能再用it