在英语语法中，定语从句是一种非常重要的结构，它能够帮助我们更清晰地描述名词或代词。通过学习和掌握定语从句的用法，我们可以使表达更加精确且富有层次感。为了巩固这一知识点，下面将提供一组精选的定语从句专项练习题，供读者参考与实践。

一、单项选择

1. The book _______ I borrowed from the library is very interesting.

A) whoB) whichC) whomD) whose

2. The man _______ you met yesterday is my uncle.

A) thatB) whoseC) whomD) where

3. Do you know the girl _______ is standing under the tree?

A) whoB) whoseC) whichD) what

4. This is the house _______ we lived in last year.

A) thatB) whereC) whenD) why

5. He is the only person _______ can solve this problem.

A) whoB) whomC) whoseD) which

二、改写句子

6. The student won the first prize. His teacher praised him.

改为定语从句：

___________________________

7. The book was written by Lu Xun. It is very popular.

改为定语从句：

___________________________

8. The man is my father. You just talked to him.

改为定语从句：

___________________________

9. The city is famous for its beautiful scenery. We visited it last summer.

改为定语从句：

___________________________

10. The movie is very moving. Everyone likes it.

改为定语从句：

___________________________

三、填空题

11. The pen _______ he used to write the letter has been lost.

12. The school _______ I graduated from is located in Beijing.

13. The book _______ on the desk belongs to Mary.

14. The boy _______ you saw yesterday is my classmate.

15. The song _______ she sang at the party was very touching.

四、综合运用

16. 根据提示完成句子：

- The man _______ is speaking now is our new teacher.

（提示：现在进行时）

17. 将以下两个句子合并成一个定语从句：

- The bag is red. You bought it yesterday.

合并后：___________________________

18. 根据上下文补全句子：

- She is the girl _______ always helps others.

（提示：经常帮助别人）

19. 写出一个含有关系副词的定语从句，描述你最喜欢的地方。

___________________________

20. 编写一段话，使用至少三个定语从句来描述你的朋友。

___________________________

以上题目旨在帮助大家熟悉定语从句的基本形式及其应用范围。希望大家能够通过这些练习，逐步提高对定语从句的理解和运用能力。如果遇到困难，可以查阅相关资料或者向老师请教，不断积累经验。祝大家学习愉快！