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英语从句专题

新概念英语第一册核心从句 | 宾语从句 | 定语从句 | 状语从句 | 用法详解

从句概述

复合句由主句和从句构成。主句是全句的主体，通常可以独立存在；从句是句子的一个成分，不能独立存在，必须由关联词引导。根据从句在句子中的作用，可以分为三大类：名词性从句、形容词性从句（定语从句）和副词性从句（状语从句）。

从句类型 作用 常见关联词
名词性从句 相当于名词，在句中作主语、宾语、表语、同位语 that, whether, if, what, who, when, where, why, how
定语从句 相当于形容词，修饰名词或代词（先行词） that, which, who, whom, whose, when, where, why
状语从句 相当于副词，修饰动词、形容词或副词，表示时间、地点、原因、条件等 when, while, as, because, if, though, until, so that

1. 宾语从句 (Object Clause)

概念

在复合句中作主句宾语的从句叫做宾语从句，通常放在及物动词、介词或形容词后面。

引导词

1. 由陈述句转化来的宾语从句，引导词用that，在口语或非正式文体中常省略
He says (that) he is a student. 他说他是一名学生。
I think (that) you are right. 我认为你是对的。
She told me (that) she would come the next day. 她告诉我她第二天会来。
2. 由一般疑问句转化来的宾语从句，引导词用whether或if，表示"是否"
I want to know if/whether he lives here. 我想知道他是否住在这里。
He asked me if/whether I could help him. 他问我是否能帮助他。
I don't know if/whether it will rain tomorrow. 我不知道明天是否会下雨。
3. 由特殊疑问句转化来的宾语从句，引导词用疑问词（what, who, when, where, why, how等）
I don't know what he is doing. 我不知道他在做什么。
Can you tell me where the station is? 你能告诉我车站在哪里吗？
He asked me when I would leave. 他问我什么时候离开。

时态一致

主句是一般现在时，从句根据实际情况用各种时态
He says that he is a student. 他说他是一名学生。
He says that he was a student three years ago. 他说他三年前是学生。
He says that he will be a doctor in the future. 他说他将来会成为一名医生。
主句是一般过去时，从句要用相应的过去时态
He said that he was a student. 他说他是一名学生。
He said that he had been a student three years before. 他说他三年前是学生。
He said that he would be a doctor in the future. 他说他将来会成为一名医生。
例外：如果从句表示的是客观真理、科学事实、自然现象等，即使主句是过去时，从句仍用一般现在时。
The teacher told us that the earth goes around the sun. 老师告诉我们地球绕着太阳转。

语序

宾语从句必须用陈述句语序，即"引导词 + 主语 + 谓语 + 其他"。

错误：I don't know what is he doing.
正确：I don't know what he is doing. 我不知道他在做什么。

错误：Can you tell me where is the station?
正确：Can you tell me where the station is? 你能告诉我车站在哪里吗？

否定转移

当主句的谓语动词是think, believe, suppose, expect等表示"认为、相信、期望"等心理活动的动词时，从句的否定要转移到主句上。

我认为他不对。
错误：I think he is not right.
正确：I don't think he is right.

2. 定语从句 (Attributive Clause)

概念

在复合句中修饰名词或代词的从句叫做定语从句。被修饰的名词或代词叫做先行词，定语从句通常放在先行词后面，由关系代词或关系副词引导。

关系代词的用法

关系代词 指代 在从句中所作成分 例句
who 指人 主语、宾语 The man who is speaking is our teacher. 正在讲话的那个人是我们的老师。
whom 指人 宾语 The man whom you met yesterday is our teacher. 你昨天遇到的那个人是我们的老师。
whose 指人或物 定语 I know the girl whose mother is a doctor. 我认识那个女孩，她妈妈是医生。
which 指物 主语、宾语 The book which I bought yesterday is very interesting. 我昨天买的那本书很有趣。
that 指人或物 主语、宾语 The film that we saw last night is wonderful. 我们昨晚看的那部电影很精彩。

关系代词的省略

当关系代词在定语从句中作宾语时，在口语或非正式文体中可以省略。

The book (that/which) I bought yesterday is very interesting. 我昨天买的那本书很有趣。
The man (who/whom/that) you met yesterday is our teacher. 你昨天遇到的那个人是我们的老师。

只能用that的情况

1. 先行词是all, everything, anything, nothing, something, little, much等不定代词时
All that we have to do is to study hard. 我们要做的一切就是努力学习。
Is there anything that I can do for you? 有什么我能为你做的吗？
2. 先行词被序数词、形容词最高级修饰时
This is the first letter that I have received from him. 这是我收到的他的第一封信。
This is the best film that I have ever seen. 这是我看过的最好的电影。
3. 先行词被the only, the very, the same, the last等修饰时
He is the only person that can help you. 他是唯一能帮助你的人。
This is the very book that I want. 这正是我想要的那本书。
4. 先行词既有人又有物时
They talked about the people and the things that they remembered in the school. 他们谈论着他们记得的学校里的人和事。

只能用which的情况

1. 非限制性定语从句（从句和主句之间有逗号隔开）
The book, which I bought yesterday, is very interesting. 这本书很有趣，是我昨天买的。
2. 介词后面指物时
The house in which we live is very old. 我们住的房子很旧。

3. 状语从句 (Adverbial Clause)

概念

在复合句中作状语的从句叫做状语从句，可以修饰动词、形容词或副词，表示时间、地点、原因、条件、让步、目的、结果、比较、方式等。

时间状语从句

引导词：when, while, as, before, after, until, since, as soon as
When he comes, I will tell him the news. 他来的时候，我会告诉他这个消息。
While I was reading, my mother was cooking. 我在看书的时候，我妈妈在做饭。
I will wait until you come back. 我会等到你回来。
I have lived here since I was born. 我从出生起就住在这里。
As soon as I get to Beijing, I will call you. 我一到北京就给你打电话。
时态规则：在时间状语从句和条件状语从句中，如果主句是一般将来时，从句要用一般现在时表示将来（主将从现）。
正确：I will call you when I arrive. 我到了会给你打电话。
错误：I will call you when I will arrive.

条件状语从句

引导词：if, unless, as long as
If it doesn't rain tomorrow, we will go to the park. 如果明天不下雨，我们就去公园。
You will fail unless you study hard. 除非你努力学习，否则你会失败。
As long as you work hard, you will succeed. 只要你努力工作，你就会成功。

原因状语从句

引导词：because, as, since, for
He didn't come to school because he was ill. 他没来上学，因为他病了。
As it is raining, we have to stay at home. 因为在下雨，我们不得不待在家里。
Since you are free today, you can help me with my English. 既然你今天有空，你可以帮我学英语。
because和so不能同时出现在一个句子里，只能用其中一个。
正确：Because he was ill, he didn't come to school.
正确：He was ill, so he didn't come to school.
错误：Because he was ill, so he didn't come to school.

让步状语从句

引导词：though, although, even if, even though
Though/Although he is young, he knows a lot. 虽然他很年轻，但他知道很多。
Even if it rains, we will still go out. 即使下雨，我们还是要出去。
though/although和but不能同时出现在一个句子里，只能用其中一个。
正确：Although he is young, he knows a lot.
正确：He is young, but he knows a lot.
错误：Although he is young, but he knows a lot.

目的状语从句

引导词：so that, in order that
He got up early so that he could catch the early bus. 他起得很早，以便能赶上早班车。
We study hard in order that we can go to a good university. 我们努力学习，为了能上一所好大学。

结果状语从句

引导词：so...that..., such...that...
so + 形容词/副词 + that 从句
such + (a/an) + 形容词 + 名词 + that 从句
He is so clever that he can work out the problem easily. 他很聪明，能轻松地算出这道题。
She is such a good girl that everyone likes her. 她是个好女孩，每个人都喜欢她。

比较状语从句

引导词：as...as..., than, the more...the more...
He is as tall as his father. 他和他爸爸一样高。
He runs faster than me. 他比我跑得快。
The more you read, the more you know. 你读得越多，知道得就越多。

间接引语 (Reported Speech)

概念

把别人说的话转述出来，叫做间接引语，实际上就是宾语从句的一种特殊形式。直接引语是直接引用别人的原话，放在引号内；间接引语不用引号，通常构成宾语从句。

时态变化

直接引语是一般现在时 → 间接引语是一般过去时
He said: "I am a student." → He said that he was a student.

直接引语是现在进行时 → 间接引语是过去进行时
He said: "I am reading." → He said that he was reading.

直接引语是一般过去时 → 间接引语是过去完成时
He said: "I bought a book yesterday." → He said that he had bought a book the day before.

直接引语是现在完成时 → 间接引语是过去完成时
He said: "I have finished my homework." → He said that he had finished his homework.

人称变化

遵循"一随主，二随宾，第三人称不更新"的原则：

  • 一随主：直接引语中的第一人称要和主句的主语一致
  • 二随宾：直接引语中的第二人称要和主句的宾语一致
  • 第三人称不更新：直接引语中的第三人称保持不变

指示代词、时间状语、地点状语和动词的变化

直接引语 间接引语 this that these those now then today that day tonight that night tomorrow the next day yesterday the day before last week the week before here there come go