The room is very dirty today.It's hard——.A.cleaning B.to clean it_英语解答

The room is very dirty today.It's hard——.A.cleaning B.to clean it C.to learning D.to clean
选什么,为什么

人气：350 ℃　时间：2019-09-10 18:31:26

解答

选B,It's hard to clean it.= To clean it is hard.
当句子的主语比较长时,可用it作为形式主语,后面用不定式作真正的主语.