My mother thinks ____ important to claen the birdge every day.A.that B.this C.it D./
问题描述：
My mother thinks ____ important to claen the birdge every day.A.that B.this C.it D./
为什么这道题选C,不应该是it is important 形容词前面应该有be动词
答
答案：C it.
1.这是find/think/feel/make等特有的结构,即：think + 形式宾语it + 宾语补足语important + 真正的宾语（不定式）to clean the bridge every day.
2.如果把宾语to clean the bridge every day直接放在think和important中间,这样会破坏结构平衡,容易造成读者理解困难.
所以先把形式宾语It放在中间,然后再把真正的宾语置后.
3.如果用it is important也可以,但是句子结构就不一样了.
此时,thinks后面为省略引导词that的宾语从句,而It为宾语从句的形式主语,is important为系表结构做从句谓语,不定式to clean the bridge every day则为从句的真正主语.