在初中英语学习中，名词性从句是一个重要的语法知识点，它包括主语从句、宾语从句、表语从句和同位语从句等类型。为了帮助同学们更好地掌握这一知识点，我们特别整理了这套包含20道经典练习题的专项练习，并附上了详细的答案解析。通过这些题目，同学们可以进一步巩固所学知识并提升解题能力。
一、名词性从句概述
名词性从句是指在句子中充当名词成分的从句，通常起到名词的作用。它们可以作为主语、宾语、表语或同位语使用。例如：
- 主语从句：What he said is true.
- 宾语从句：I don't know what you mean.
- 表语从句：The problem is where we can find the answer.
- 同位语从句：We all know the fact that water freezes at 0°C.
二、20道练习题及答案解析
1. 题目：
She didn't tell me ______ she had been to Beijing before.
A. if B. whether C. that D. why
答案解析：
正确答案为B。"whether"用于引导宾语从句，表示“是否”。本题考查的是宾语从句中引导词的选择。
2. 题目：
The question is ______ they will come tomorrow.
A. that B. if C. whether D. what
答案解析：
正确答案为C。"whether"引导表语从句，表示“是否”。这里需要一个连接词来引导表语从句。
3. 题目：
He told us ______ the news was true.
A. that B. which C. who D. whose
答案解析：
正确答案为A。"that"引导宾语从句，用来补充说明新闻的真实性。
4. 题目：
It is certain ______ we will succeed in the end.
A. that B. when C. why D. how
答案解析：
正确答案为A。"that"引导主语从句，表示“我们最终会成功”是确定的事实。
5. 题目：
Do you remember ______ he came here?
A. where B. when C. what D. how
答案解析：
正确答案为B。"when"引导宾语从句，表示“他什么时候来这里”。
6. 题目：
The reason ______ he gave for being late was unbelievable.
A. why B. that C. which D. where
答案解析：
正确答案为B。"that"引导定语从句，修饰先行词“reason”。
7. 题目：
It's strange ______ he didn't come yesterday.
A. because B. that C. why D. when
答案解析：
正确答案为B。"that"引导主语从句，表示“他昨天没来是奇怪的”。
8. 题目：
I don't understand ______ he wants to say.
A. that B. what C. which D. why
答案解析：
正确答案为B。"what"引导宾语从句，表示“他想说什么”。
9. 题目：
The idea ______ we should help each other is good.
A. that B. which C. where D. why
答案解析：
正确答案为A。"that"引导同位语从句，解释“我们应该互相帮助”的想法。
10. 题目：
She asked me ______ I would go with her.
A. if B. whether C. that D. what
答案解析：
正确答案为A。"if"引导宾语从句，表示“我是否会和她一起去”。
11. 题目：
The book ______ he bought yesterday is very interesting.
A. that B. which C. where D. who
答案解析：
正确答案为A。"that"或"which"均可引导定语从句，修饰先行词“book”。
12. 题目：
The reason ______ he was late was that he missed the bus.
A. why B. that C. which D. where
答案解析：
正确答案为A。"why"引导定语从句，修饰先行词“reason”。
13. 题目：
It's clear ______ he has worked hard.
A. that B. when C. why D. how
答案解析：
正确答案为A。"that"引导主语从句，表示“他努力工作是显而易见的”。
14. 题目：
The teacher explained ______ the students could understand the lesson better.
A. so that B. in order that C. that D. because
答案解析：
正确答案为C。"that"引导宾语从句，表示“老师解释的内容”。
15. 题目：
He told me ______ he would finish his homework.
A. when B. where C. that D. why
答案解析：
正确答案为C。"that"引导宾语从句，表示“他将完成作业”。
16. 题目：
The news ______ our team won the game made everyone excited.
A. that B. which C. where D. why
答案解析：
正确答案为A。"that"引导同位语从句，解释“我们的团队赢得了比赛”的消息。
17. 题目：
The fact ______ the earth moves around the sun is well known.
A. that B. which C. where D. why
答案解析：
正确答案为A。"that"引导同位语从句，解释“地球绕太阳运行”的事实。
18. 题目：
She didn't tell me ______ she had seen the movie.
A. if B. whether C. that D. when
答案解析：
正确答案为B。"whether"引导宾语从句，表示“是否”。
19. 题目：
The reason ______ he was absent was illness.
A. why B. that C. which D. where
答案解析：
正确答案为A。"why"引导定语从句，修饰先行词“reason”。
20. 题目：
It's important ______ we should study hard.
A. that B. when C. why D. how
答案解析：
正确答案为A。"that"引导主语从句，表示“我们应该努力学习是很重要的”。
三、总结
通过以上20道练习题，我们可以看到名词性从句在英语中的重要性。希望大家能够熟练掌握各类从句的用法，并灵活运用到实际学习和考试中。如果还有疑问，欢迎随时交流！
---
希望这份练习题对大家有所帮助！
