模块 05句子结构与变式

28 主谓一致：找到主语核心，再让限定动词与它匹配

主谓一致最容易错在“看错主语”，而不是不会加 -s。真正有效的方法是先找承担主语功能的完整短语，再找其中决定单复数的核心词，最后检查限定动词或第一个助动词。

约 15 分钟 19 个复习节点 学习中

本章学习目标

学完本章，你应该能够：

  1. 找出长主语中的核心词，不受介词短语和插入信息干扰。
  2. 掌握语法一致、意义一致和就近一致的使用条件。
  3. 处理并列主语、不定代词、数量表达、集合名词和 there be。
  4. 判断定语从句、倒装结构中的一致关系。
  5. 写作时用稳定流程检查主谓一致并主动改写别扭结构。

学前诊断：离动词最近的名词决定单复数吗

选择：The list of items is / are on the desk. 为什么 items 是复数，却不能直接决定谓语形式？

答案与提示

选 is。完整主语是 The list of items，其中决定数量的核心名词是单数 list；of items 只是修饰它的介词短语。主谓一致先找主语核心，不能让附近的复数名词吸引走判断。

1. 一致发生在哪里

英语中的主谓一致主要体现在：

  1. 一般现在时中，第三人称单数动词通常加 -s/-es。
  2. be 在现在和过去使用不同形式：am/is/are，was/were。
  3. 完成、进行、被动等结构中，第一个承担限定性的助动词与主语配合。

比较：

  • The student works carefully.
  • The students work carefully.
  • The student has been working carefully.
  • The students have been working carefully.

后两句中，真正变化的是第一个助动词 has/have，不是最后的 working。

2. 三种一致原则

原则依据典型情况
语法一致主语核心的语法单复数the list of names is
意义一致说话人把主语理解为整体还是多个成员the team is/are
就近一致谓语与最近的并列项配合either the teachers or the student is

三种原则不是互相竞争的口诀。普通情况优先语法一致；特定集合、数量或并列结构才考虑意义或就近关系。

3. 第一步：找到真正的主语核心

3.1 介词短语中的名词不是主语核心

The quality of the materials has improved.

  • 完整主语：The quality of the materials
  • 核心词：单数 quality
  • 谓语：has improved

中间的复数 materials 离动词更近，却不控制一致。

再看：

The results of the survey show a clear pattern.

核心词是复数 results，所以用 show。

不要让离动词最近的名词替真正的主语作决定。

3.2 插入成分不改变核心

The manager, together with two assistants, is attending the meeting.

together with two assistants 是附加信息。类似表达包括：

  • along with
  • as well as
  • in addition to
  • including
  • accompanied by

它们不像 and 那样组成复数并列主语，谓语通常跟前面的核心主语一致。

3.3 后置定语也不改变主语核心

The students waiting near the entrance are from another school.

核心词 students 是复数；waiting near the entrance 只是后置修饰。

4. 名词性结构作主语

4.1 不定式和动名词结构

一个行为或活动整体作主语时，通常按单数处理：

  • Reading every day helps.
  • To change the schedule now seems risky.

若两个真正独立的活动由 and 并列，可用复数：

Reading and writing are essential skills.

4.2 主语从句

名词性从句表达一整件事时通常按单数：

What she suggested makes sense.

That several pages are missing is obvious.

某些 what 从句后的补语为明显复数时，真实英语中可见意义一致的复数用法，如 What we need are more volunteers；基础写作若无把握，可改为 We need more volunteers 或 The people we need are ...。

5. 不定代词和数量词

5.1 通常按单数

everyone, everybody, someone, somebody, anyone, anybody, no one, nobody, each, either, neither

  • Everyone is ready.
  • Each of the answers has been checked.
  • Neither of the options seems ideal.

they/their 可以回指单数不定代词，但不改变谓语的单数形式：

Everyone is responsible for their own work.

5.2 根据 of 后名词决定

all, some, most, half, a lot, plenty, none 等可指可数复数或不可数整体：

  • Some of the information is outdated.
  • Some of the files are missing.

none 在现代英语中可接单数或复数，取决于意义和语体：

  • None of the information is useful.
  • None of the students are ready.

5.3 a number of 与 the number of

  • A number of students are absent. = 若干学生
  • The number of students is increasing. = 学生人数

5.4 one of

One of the students is absent.

核心是 one，不是复数 students。

6. 并列主语

6.1 A and B 通常用复数

The instructor and the assistant are preparing the room.

6.2 表示同一个人、事物或整体概念时可用单数

The writer and editor of the journal is speaking today.

这里只有一个人，同时具有两个身份；只有第一个身份前有冠词。

比较：

The writer and the editor of the journal are speaking today.

两个冠词通常表示两个人。

某些固定组合被理解为一个整体时也可用单数，但这种选择依赖语境。写作时若可能误解，直接改写比套口诀更稳妥。

6.3 each/every 分别限定并列项

Every student and every teacher is required to register.

强调逐个成员时，常用单数。

7. 就近一致结构

7.1 or / either ... or / neither ... nor

谓语通常与离它最近的并列项一致：

  • Either the teachers or the student is responsible.
  • Either the student or the teachers are responsible.

7.2 not only ... but also

  • Not only the manager but also the assistants are attending.
  • Not only the assistants but also the manager is attending.

如果单复数混排让句子读起来别扭，可以把复数项放近谓语，或改写：

The manager and the assistants are all attending.

8. 数量作为整体

时间、距离、金额、重量等被看成一个整体量时，常用单数：

  • Ten kilometres is a long distance to walk.
  • Two hours is enough.
  • Five hundred yuan is the total cost.

若强调其中多个单位或个体，则可能用复数：

The last two hours were extremely stressful.

区别来自意义，不是只看数字后有没有 -s。

9. 形式与意义不一致的名词

9.1 看似复数但通常按单数

  • news：The news is encouraging.
  • mathematics：Mathematics is required.
  • physics：Physics is difficult for some students.

9.2 形式单一但通常表示复数成员

  • police：The police are investigating.
  • people：Many people are waiting.

9.3 单复数同形

means, series, species 等要根据限定词和意义判断：

  • This means is effective.
  • These means are effective.
  • A new series is available.
  • Several series are available.

9.4 data 等用法变化

在传统正式科学语体中，data 常视为 datum 的复数：The data are consistent. 在一般现代英语和部分专业语体中，也常把它当集合或不可数信息：The data is consistent. 应遵循学科、机构或写作规范，并保持全文一致。

10. 集合名词：整体还是成员

team, committee, family, government, staff 等可以表示一个整体，也可以突出其中成员。

  • 整体：The committee has reached a decision.
  • 成员：The committee are divided in their opinions.

英式英语较常使用复数突出成员；美式英语通常更偏单数整体，必要时改写为 committee members are ...。

11. there be：真正主语在后面

There is a problem with the schedule.

there 是形式成分，真正需要介绍的名词在 be 后。标准书面英语通常与后面最近的名词短语配合：

  • There is a problem.
  • There are several problems.

混合单复数列表会造成不自然：

There is a notebook and two folders on the desk.

这在口语中常见，但正式写作可改写为：

  • A notebook and two folders are on the desk.
  • There are two folders and a notebook on the desk.

规则允许的结构若让一致关系难读，改写通常比争论 `is/are` 更好。

12. 定语从句中的一致

关系代词的单复数由先行词决定：

  • the student who works here
  • the students who work here

高频难点：

She is one of the students who work hardest.

who 通常回指复数 students，所以用 work。

She is the only one of the students who works remotely.

语义上 who 限定唯一的 one，通常用 works。

13. 倒装和远距离主语

On the wall are several photographs.

地点状语前置后，真正主语 several photographs 在动词后，因此用 are。

Among the main causes is a lack of training.

真正主语是单数 a lack of training，所以用 is。

阅读时不要默认动词前最近的名词就是主语。

14. 主谓一致六步检查法

  1. 划出分句边界。
  2. 找每个分句的限定动词或第一个助动词。
  3. 找完整主语，并圈出核心词。
  4. 暂时删去介词短语、定语从句和插入成分。
  5. 判断是否属于并列、数量、集合、there be 等特殊结构。
  6. 朗读检查，并在结构别扭时主动改写。

例句：

The effect of the new rules on small businesses has not been fully examined.

  • 限定动词词组：has not been examined
  • 完整主语：The effect of the new rules on small businesses
  • 核心词：单数 effect
  • 所以用 has。

15. 高频错误

  1. The list of items are long. → The list of items is long.
  2. Each of the students have a copy. → Each ... has a copy.
  3. A number of errors has appeared. → A number of errors have appeared.
  4. The number of errors have increased. → The number ... has increased.
  5. The manager, along with two assistants, are attending. → ... is attending.
  6. There is several reasons. → There are several reasons.

16. 快速复习清单

  • 一致发生在主语与限定动词/第一个助动词之间。
  • 先找主语核心，不被中间名词带偏。
  • and 通常构成复数；as well as 等通常不改变核心主语。
  • 不定式、动名词和主语从句表达一件事时通常按单数。
  • some/all/most 等依据 of 后名词决定。
  • a number of 用复数，the number of 用单数。
  • 集合名词看整体/成员、英语变体和语体。
  • 就近一致或 there be 结构别扭时，可以改写。

17. 自检题

题目

  1. 选择：The quality of these products has / have improved.
  2. 选择：Each of the reports needs / need revision.
  3. 选择：Some of the information is / are missing.
  4. 选择：Some of the files is / are missing.
  5. 选择：A number of students is / are waiting.
  6. 选择：The number of students is / are increasing.
  7. 选择：Either the assistants or the manager is / are attending.
  8. 改写使句子更自然：There is a laptop and three tablets in the cabinet.
  9. 选择：She is one of the researchers who works / work remotely.
  10. 解释差别：The committee has agreed 与 The committee are divided。
  11. 改错：The main cause of the delays are unclear.
  12. 用六步法分析：The results of the latest survey on working habits show a significant change.
答案与解析
  1. has。主语核心是单数 quality，of these products 不控制一致。
  2. needs。核心是不定代词 each，通常按单数。
  3. is。information 是不可数名词。
  4. are。files 是复数可数名词。
  5. are。a number of 表示“若干”，后接复数概念。
  6. is。主语是“数量”这个单数整体。
  7. is。就近项 the manager 是单数。
  8. 示例：There are three tablets and a laptop in the cabinet. 或 A laptop and three tablets are in the cabinet.
  9. work。who 通常回指复数先行词 researchers。
  10. 前者把委员会看作一个整体作出决定；后者突出成员意见不一，并体现英式英语常见的复数集合用法。
  11. The main cause of the delays is unclear. 核心词是单数 cause。
  12. 限定动词是 show；完整主语是 The results of the latest survey on working habits；核心词 results 为复数，两个介词短语均为修饰，因此用复数 show。
完成本章后

把“看懂”变成“能独立判断”

确认你已经完成自检题，并能说出本章的判断步骤。