🔗 复合句
宾语从句 · 状语从句 · 定语从句 · 主语从句与表语从句
考点一：宾语从句
🔹 宾语从句三要素
| 要素 | 说明 | 举例 |
|---|---|---|
| 引导词 | 连接主句和从句的词 | that, if/whether, 疑问词 |
| 语序 | 宾语从句用陈述语序 | 主语 + 谓语 |
| 时态 | 主句和从句时态要呼应 | 主现从任意，主过从过 |
🔹 引导词的选择
| 从句类型 | 引导词 | 举例 |
|---|---|---|
| 陈述句变宾语从句 | that（可省略） | He said (that) he was a student. 他说他是学生。 |
| 一般疑问句变宾语从句 | if / whether（是否） | I don't know if/whether he will come. 我不知道他是否会来。 |
| 特殊疑问句变宾语从句 | 原疑问词（what, who, where, when, how, why 等） | Can you tell me where he lives? 你能告诉我他住在哪里吗？ |
🔹 宾语从句的时态呼应
| 主句时态 | 从句时态 | 举例 |
|---|---|---|
| 一般现在时 | 根据实际需要选择时态 | I think he is right. / I think he will come. |
| 一般过去时 | 相应的过去时态 | He said he was a student.（一般现在→一般过去） He said he had finished it.（一般过去→过去完成） He said he would come.（一般将来→过去将来） |
| 一般过去时（客观真理） | 仍用一般现在时 | The teacher told us the earth goes around the sun. |
if 与 whether 的区别：
以下情况只能用 whether，不能用 if：
① 与 or not 连用时：I don't know whether or not he will come.
② 作介词宾语时：It depends on whether he agrees.
③ 后接不定式时：I don't know whether to go.
④ 引导主语从句时：Whether he will come is unknown.
宾语从句三要素：引导词、语序、时态；
陈述句用that引，一般疑问if/whether；
特殊疑问用原词，从句一律陈述序；
主现从任意，主过从过去；
客观真理永不变，一般现在记心间。
选择正确答案：
1. Could you tell me ______ the nearest hospital is?（where / how）
2. He asked me ______ I liked English.（that / if）
3. She said she ______ to Beijing the next day.（will go / would go）
4. The teacher told us that light ______ faster than sound.（traveled / travels）
1. where — 问"最近的医院在哪里"，用 where。
2. if — 一般疑问句变宾语从句用 if/whether。
3. would go — 主句 said 是过去时，从句 will 变 would。
4. travels — 光比声音快是客观真理，用一般现在时。
考点二：状语从句
🔹 时间状语从句
| 连词 | 含义 | 举例 |
|---|---|---|
| when | 当……时候 | I was doing homework when he came in. |
| while | 在……期间（持续动作） | While I was reading, he was sleeping. |
| as | 一边……一边…… | He sang as he walked. |
| before | 在……之前 | Think twice before you act. |
| after | 在……之后 | I went home after I finished my work. |
| since | 自从 | I have lived here since 2010. |
| until / till | 直到…… | I waited until he came back. |
| as soon as | 一……就…… | I'll call you as soon as I arrive. |
🔹 条件状语从句
- if（如果）：If it rains tomorrow, we won't go out.
- unless（除非 = if...not）：Unless you study hard, you will fail. = If you don't study hard, you will fail.
- as long as（只要）：As long as you try, you will succeed.
🔹 原因状语从句
- because（因为，语气最强）：I stayed at home because it rained.
- since（既然）：Since you are here, let's begin.
- as（由于）：As it was late, we went home.
🔹 让步状语从句
- although / though（虽然）：Although he is old, he is still healthy.
- even though / even if（即使）：Even if it rains, I will go.
🔹 结果状语从句
- so...that...（如此……以至于……）：He is so tired that he can't walk.
- such...that...（如此……以至于……）：It is such a good book that everyone likes it.
🔹 目的状语从句
- so that（以便，为了）：He got up early so that he could catch the bus.
- in order that（为了）：I study hard in order that I can pass the exam.
"主将从现"原则：
在时间状语从句和条件状语从句中，如果主句用一般将来时，从句要用一般现在时代替一般将来时。
✅ If it rains tomorrow, I will stay at home.（从句用一般现在时）
❌ If it will rain tomorrow, I will stay at home.
✅ I'll call you as soon as I arrive.（从句用一般现在时）
❌ I'll call you as soon as I will arrive.
although/though 不能与 but 同时使用：
✅ Although he is old, he is healthy.
✅ He is old, but he is healthy.
❌ Although he is old, but he is healthy.
时间when/while/as，before/after/since/until；
条件if/unless/as long as，主将从现要牢记；
原因because/since/as，让步although/though；
结果so...that/such...that，目的so that为了啥；
although和but不同现，because和so不并用。
选择正确答案：
1. I will go to the park if it ______ tomorrow.（doesn't rain / won't rain）
2. ______ he is young, he knows a lot.（Although / But）
3. He was ______ tired ______ he fell asleep at once.（so; that / such; that）
4. I have lived here ______ I was born.（since / for）
1. doesn't rain — 条件状语从句"主将从现"。
2. Although — 表示"虽然"，不能与 but 同时使用。
3. so; that — so + 形容词 + that，表示"如此……以至于"。
4. since — since + 时间点，表示"自从"。
考点三：定语从句
🔹 定语从句的基本概念
定语从句是修饰名词或代词的从句，被修饰的词叫先行词，引导定语从句的词叫关系词。
例如：The boy who is reading is Tom.（who is reading 修饰 the boy）
正在读书的那个男孩是汤姆。
🔹 关系代词
| 关系代词 | 先行词 | 在从句中的作用 | 举例 |
|---|---|---|---|
| who | 人 | 主语、宾语 | The man who is standing there is my father. |
| whom | 人 | 宾语 | The girl whom I met yesterday is Lucy. |
| whose | 人/物 | 定语 | The boy whose father is a doctor is Tom. |
| which | 物 | 主语、宾语 | The book which I bought is interesting. |
| that | 人/物 | 主语、宾语 | The man that is standing there is my father. The book that I bought is interesting. |
🔹 关系副词
| 关系副词 | 先行词 | 在从句中的作用 | 举例 |
|---|---|---|---|
| where | 地点名词 | 地点状语 | This is the school where I studied. |
| when | 时间名词 | 时间状语 | I'll never forget the day when I met you. |
| why | reason | 原因状语 | That's the reason why he was late. |
🔹 只能用 that 不能用 which 的情况
- ① 先行词被最高级修饰时：This is the best film that I have ever seen.
- ② 先行词被序数词修饰时：The first thing that I should do is homework.
- ③ 先行词被 all, every, any, no, the only, the very 等修饰时：
All that he said is true. - ④ 先行词既有人又有物时：He talked about the people and things that he saw.
- ⑤ 先行词是不定代词（something, anything, nothing, everything 等）时：
Is there anything that I can do for you?
关系代词作宾语时可以省略：
The book (that/which) I bought is interesting.（that/which 作宾语，可省略）
The man (who/whom/that) I met is a teacher.（who/whom/that 作宾语，可省略）
关系代词作主语时不能省略：
The man who is standing there is my father.（who 作主语，不能省略）
定语从句修饰名，先行词后关系词；
who/whom修饰人，which修饰物，that人物通用；
where地点when时间why原因，关系副词作状语；
最高级序数词all/every/any，只用that不用which；
关系词作宾语可省略，作主语千万不能省。
用适当的关系词填空：
1. The girl ______ is singing is my sister.
2. This is the best movie ______ I have ever seen.
3. I still remember the day ______ I first came to this school.
4. The house ______ roof is red is mine.
1. who/that — 先行词是人（the girl），关系词在从句中作主语。
2. that — 先行词被最高级 best 修饰，只能用 that。
3. when — 先行词是时间名词 the day，关系词在从句中作时间状语。
4. whose — 表示"……的"，the house 的 roof，用 whose。
考点四：主语从句与表语从句
🔹 主语从句
在复合句中充当主语的从句叫主语从句，通常放在主句谓语动词之前，或用 it 作形式主语。
| 引导词 | 举例 |
|---|---|
| that | That he will come is certain. = It is certain that he will come. 他会来是确定的。 |
| whether | Whether he will come is unknown. 他是否会来还不知道。 |
| what | What he said is true. 他说的话是真的。 |
| who | Who will go is not decided yet. 谁去还没决定。 |
🔹 常见的 it 作形式主语的句型
- It is + 形容词 + that 从句
It is important that we should study hard. 我们应该努力学习，这很重要。 - It is + 名词 + that 从句
It is a fact that the earth goes around the sun. 地球绕太阳转是事实。 - It is + 过去分词 + that 从句
It is reported that the meeting has been put off. 据报道会议已被推迟。
🔹 表语从句
在复合句中充当表语的从句叫表语从句，放在系动词（be, look, seem, remain 等）之后。
| 引导词 | 举例 |
|---|---|
| that | The fact is that we have lost the game. 事实是我们输了比赛。 |
| whether | The question is whether he will come. 问题是他是否会来。 |
| what | That's what I want to say. 那就是我想说的。 |
| because | That's because he was ill. 那是因为他病了。 |
| why | That's why he was late. 那就是他迟到的原因。 |
That's because... vs That's why...：
That's because... 表示"那是因为……"（后接原因）
That's why... 表示"那就是为什么……"（后接结果）
He was ill. That's why he was absent.（他病了，那就是他缺席的原因。）
He was absent. That's because he was ill.（他缺席了，那是因为他病了。）
主语从句中引导词 if 和 whether：
引导主语从句时只能用 whether，不能用 if。
✅ Whether he will come is unknown.
❌ If he will come is unknown.
主语从句作主语，it形式主语来代替；
that/whether/what/who来引导，主语从句不用if；
表语从句系动词后，that/whether/what/because/why；
because后接原因，why后接结果要分清。
选择正确答案：
1. ______ he said at the meeting surprised everyone.（What / That）
2. It is important ______ we should protect the environment.（what / that）
3. He was late. That's ______ he missed the bus.（because / why）
4. The question is ______ we can finish the work on time.（that / whether）
1. What — what 在从句中作 said 的宾语，"他在会上说的话"。
2. that — It is important that... 是固定句型，that 引导主语从句。
3. because — "他迟到了"是结果，后面接原因"因为他错过了公交车"。
4. whether — "问题是他是否能按时完成"，表示"是否"用 whether。
考点五：同位语从句
🔹 同位语从句的定义
同位语从句用来对前面的抽象名词进行解释说明，说明该名词的具体内容。常跟在 news, fact, idea, hope, thought, question, order, belief, suggestion, truth, problem 等名词后面。
🔹 同位语从句的引导词
| 引导词 | 举例 |
|---|---|
| that（最常见） | The news that he passed the exam made us happy. 他通过考试的消息让我们很高兴。 |
| whether | The question whether we should go has not been decided. 我们是否应该去的问题还没有决定。 |
| what | I have no idea what he is doing. 我不知道他在做什么。 |
| when / where / how | The question how we can get there is still unknown. 我们怎样到达那里的问题仍然未知。 |
🔹 同位语从句与定语从句的区别
| 比较项 | 同位语从句 | 定语从句 |
|---|---|---|
| 功能 | 解释说明名词的内容 | 修饰限定名词 |
| that 的作用 | 只起连接作用，不作成分，不能省略 | 作主语或宾语，作宾语时可省略 |
| 先行词 | 抽象名词（news, fact, idea 等） | 任何名词或代词 |
| 能否用 which 替换 that | 不能 | 指物时可以 |
对比：
同位语从句：The news that he won the prize is true.（that 不作成分，解释 news 的内容）
定语从句：The news that he told me is true.（that 作 told 的宾语，修饰 news）
判断同位语从句还是定语从句的方法：
① 看 that 在从句中是否作成分：不作成分→同位语从句；作成分→定语从句。
② 看能否在名词和从句之间加"是"：能加→同位语从句；不能加→定语从句。
The news that our team won = The news is that our team won.（✅ 同位语从句）
The news that he told me ≠ The news is that he told me.（❌ 定语从句）
同位语从句解释名词内容，定语从句修饰限定名词；
that不作成分是同位语，that作成分是定语从句；
名词和从句之间加个"是"，通顺就是同位语从句；
news/fact/idea/hope后面跟，同位语从句最常见。
判断下列句子中的从句是同位语从句还是定语从句：
1. The idea that he put forward is very good.（______）
2. The idea that we should have a meeting is very good.（______）
3. I had no idea that you were here.（______）
4. The book that I bought yesterday is interesting.（______）
1. 定语从句 — that 在从句中作 put forward 的宾语，修饰 the idea。
2. 同位语从句 — that 不作成分，解释 the idea 的具体内容是"我们应该开个会"。
3. 同位语从句 — that 不作成分，解释 idea 的内容是"你在这里"。
4. 定语从句 — that 在从句中作 bought 的宾语，修饰 the book。
考点六：复合句综合辨析
🔹 各类从句对比总结
| 从句类型 | 在句中作用 | 常见引导词 | 举例 |
|---|---|---|---|
| 主语从句 | 作主语 | that, whether, what, who, how 等 | What he said is true. |
| 宾语从句 | 作宾语 | that, if/whether, what, who, how 等 | I know that he is right. |
| 表语从句 | 作表语 | that, whether, what, because, why 等 | The fact is that we lost. |
| 同位语从句 | 解释名词内容 | that, whether, what, how 等 | The news that he won is true. |
| 定语从句 | 修饰名词 | who, whom, whose, which, that, where, when, why | The boy who is reading is Tom. |
| 状语从句 | 作状语 | when, while, if, because, although, so that 等 | I'll go if it doesn't rain. |
🔹 快速判断从句类型的方法
- 第一步：找出从句在句中的位置和作用。
- 第二步：
- 从句在动词/介词后面 → 宾语从句
- 从句在系动词后面 → 表语从句
- 从句在句首作主语 → 主语从句
- 从句在名词后面解释内容 → 同位语从句
- 从句在名词后面修饰限定 → 定语从句
- 从句表示时间/条件/原因等 → 状语从句
what 与 that 的区别：
what = the thing(s) that，在从句中作成分（主语/宾语/表语）。
that 在名词性从句中不作成分，只起连接作用。
✅ What he said is true.（what 作 said 的宾语）
✅ I believe that he is honest.（that 不作成分）
❌ I believe what he is honest.（what 无法作成分，应用 that）
where 引导不同从句的区别：
定语从句：This is the school where I studied.（where = in which，修饰 school）
状语从句：Where there is a will, there is a way.（where 引导地点状语从句）
宾语从句：I don't know where he lives.（where 引导宾语从句）
六大从句要分清，位置作用是关键；
动词后面是宾语，系动词后是表语；
句首作主语从句，名词后面看内容；
解释内容同位语，修饰限定定语从句；
时间条件原因让步，统都是状语从句；
what作成分that不作，判断从句第一招。
判断下列句子中从句的类型：
1. It is certain that he will come.（______）
2. The reason why he was late is that he missed the bus.（______）
3. I don't know where he lives.（______）
4. If it rains tomorrow, we won't go out.（______）
5. The boy who is standing there is my brother.（______）
1. 主语从句 — it 是形式主语，that he will come 是真正的主语。
2. why he was late 是定语从句（修饰 the reason）；that he missed the bus 是表语从句（在系动词 is 后面）。
3. 宾语从句 — where he lives 在动词 know 后面作宾语。
4. 条件状语从句 — if 引导条件状语从句，表示"如果"。
5. 定语从句 — who is standing there 修饰 the boy。