that从句一般不能充当介词宾语,但偶尔可以作except,but,besides,in的宾语
eg:He is a good student except that he is a little bit careless.
He differed from his classmates in that he devoted his spare time to reading.
其他介词后面需要用that从句作宾语时,必须用it作形式宾语.
eg:You may depend on it that I shall always help you.