单句指错 求大神解答21. Great changes have been taken place in our cou

单句指错 求大神解答
21. Great changes have been taken place in our country in the last twenty years.
A B C D
22. As the Children’s Day is drawing near , all children are getting more and more exciting
A B C D
23. You are a new driver, aren’t you ? In that case , you should drive careful and slowly
A B C D
24. There are always a shortage of water in north China.
A B C D
25. The book is so bored that I returned to the library without finishing it.
A B C D
请说明怎么改~谢谢~