1．我们中学生在保护环境方面起重要的作用。(role)

　 We high school students have an important 　　　41　　　 　environment protection.

1)．As he was weak, he quitted his work.

　　 　31　 　weak, he quitted his work.

2)．He wishes to make friends with anyone who shares his hobbies.

　　 He wishes to be friends with those 　32　 　his hobbies.

3)．We think it is out duty to create a good future for our motherland.

　　 We regard 　33　 　　34　 　our duty to create a good future for out motherland.

4)．As they walked, they sang songs.

　　 They walked 　35　 　songs.

5)．It was fortunate that all his family had been brought to safety before their house fell apart.

　　 　36　 , all his family had been brought to safety before his house fell apart.

6)．The attraction is well worth visiting again.

　　 　37　 　　38　 　worthwhile to visit the attraction a second time.

7)．Would you mind if I opened the window?

　　 Would you mind 　39　 　　40　 　the window?

30．Theme parks are 　　　　　(profit) business.

29．　　　　 (成年人) learn more slowly than kids.

28．The twins are 　　　　(similar) dressed.

27．She only buys the best 　　　　　(牌子) of clothes.

26．They asked to 　　　　　(取代) Bob with George.

25．My 　　　　　(inspire) came from the book.

24．Lack of 　　　　(解释) results in misunderstanding.

23．The 　　　　　(大多数) of them are friendly.