动词语气
简介
语气(Mood)是动词的语法范畴,表达说话人对所说内容的 态度。
英语动词有 3 种基本语气:
- 陈述语气(Indicative Mood)
- 祈使语气(Imperative Mood)
- 虚拟语气(Subjunctive Mood)
| 语气 | 表达内容 | 典型示例 |
|---|---|---|
| 陈述语气 | 陈述事实、提出疑问 | He is a student.(他是一名学生。) |
| 祈使语气 | 表达命令、请求、建议 | Close the door.(把门关上。) |
| 虚拟语气 | 表达假设、愿望、建议要求 | If I were you, I would go.(如果我是你,我就会去。) |
陈述语气
陈述语气 用于陈述事实、描述状态、提出疑问,是英语中使用最频繁的语气。
时态、语态、人称均按 常规规则 变化(详见 动词时态、被动)。
- The Earth goes around the Sun.(地球绕着太阳转。)
- He didn't come yesterday.(他昨天没来。)
- Are you a student?(你是学生吗?)
祈使语气
祈使语气 用于表达 命令、请求、建议、禁止 或 指示。
形式
祈使句通常 省略主语(默认为 you),动词使用 原形。
| 类型 | 形式 | 示例 |
|---|---|---|
| 肯定 | 动词原形 ... | Close the door.(把门关上。) |
| 否定 | Don't + 动词原形 ... | Don't be late again.(别再迟到了。) |
| 婉转 | Please + 动词原形 / 动词原形 ..., please | Please sit down.(请坐。) |
| 建议自身 | Let me + 动词原形 | Let me try.(让我试试。) |
| 建议双方 | Let's + 动词原形 | Let's go now.(我们现在走吧。) |
| 第三人称 | Let him + 动词原形 | Let him decide.(让他来决定。) |
加强语气
句首加 do 可加强祈使语气,多用于请求或催促。
- Do sit down.(请务必坐下。)
- Do come early.(请一定早点来。)
虚拟语气
虚拟语气 表示与 事实相反 的假设、不可能实现的愿望、或主观的建议要求。
与事实相反的条件句
条件状语从句(if-clause)和 主句 的虚拟形式根据时间不同分为 3 类。
| 时间 | 从句(if-clause) | 主句 | 示例 |
|---|---|---|---|
| 与现在事实相反 | 过去时态(be 用 were) | would / could / should / might + 动词原形 | If I were you, I would go.(如果我是你,我就会去。) |
| 与过去事实相反 | had + 过去分词 | would / could / should / might + have + 过去分词 | If I had known, I would have come.(如果我早知道,我就来了。) |
| 与将来事实相反 | 过去时态 / should + 动词原形 / were to + 动词原形 | would / could / should / might + 动词原形 | If it should rain tomorrow, I would stay home.(如果明天下雨,我就待在家。) |
- If I were rich, I would travel the world.(如果我富有,我就会环游世界。)(与现在相反)
- If he had studied harder, he would have passed.(如果他当初更用功,就通过了。)(与过去相反)
- If the sun were to rise in the west, I would believe you.(如果太阳从西边升起,我就相信你。)(与将来相反)
错综时间条件句
从句和主句的时间 不一致 时,各自按对应规则使用虚拟形式。
- If you had taken my advice, you would not be in trouble now.(如果你当初听了我的建议,现在就不会有麻烦。)
(从句:与过去相反;主句:与现在相反)
含蓄条件句
条件不通过 if 引出,而通过 介词短语、without、but for、otherwise 等暗示。
- Without your help, I would have failed.(没有你的帮助,我就失败了。)
- But for the rain, we would have gone out.(要不是下雨,我们就出门了。)
- He didn't tell me; otherwise I would have come.(他没告诉我,否则我就来了。)
倒装条件句
省略 if,将 were、had、should 提到 句首(详见 倒装)。
- Were I you, I would go.(如果我是你,我就会去。)(= If I were you)
- Had I known, I would have come.(如果我早知道,我就来了。)(= If I had known)
- Should it rain, we would cancel the trip.(万一下雨,我们就取消这次出行。)(= If it should rain)
在名词性从句中
在主语从句和表语从句中
句型 It is + 表语 + that 从句:表语为 necessary, important, essential, vital, urgent, advisable, … 时,从句谓语用 (should) + 动词原形。
- It is necessary that he (should) be present.(他有必要到场。)
- It is important that we (should) act at once.(我们立即行动很重要。)
在宾语从句中
含 建议、要求、命令 之意的动词后接的宾语从句,谓语用 (should) + 动词原形。
常见动词可用 「一坚持,二命令,三建议,四要求」 记忆:
- 坚持:insist
- 命令:order, command, demand
- 建议:suggest, advise, propose, recommend
- 要求:request, require, ask, desire
- The teacher insists that we (should) finish the work.(老师坚持要我们完成这项工作。)
- He suggested that she (should) see a doctor.(他建议她去看医生。)
- insist 表示 「坚持认为」 时(陈述事实),用陈述语气,不用虚拟。
- suggest 表示 「暗示、表明」 时,用陈述语气。
- He insisted that he was innocent.(他坚称自己是无辜的。)(坚持认为)
- The smile suggested that he was happy.(那笑容表明他很开心。)(暗示)
在同位语从句和表语从句中
由 suggestion, advice, order, request, demand, idea, proposal, … 引导的同位语从句和表语从句,谓语用 (should) + 动词原形。
- His suggestion that we (should) leave early was accepted.(他关于我们早点离开的建议被采纳了。)
- My advice is that you (should) study harder.(我的建议是你要更用功学习。)
在状语从句中
让步状语从句
由 whatever, whoever, however, … 引导,谓语可用 may + 动词原形 表虚拟。
- Whatever he may say, don't believe him.(无论他说什么,都别信他。)
目的状语从句
由 so that, in order that, lest, for fear that 引导,谓语用 may/might/should + 动词原形。
- He spoke slowly so that we might understand him.(他说得很慢,好让我们听懂。)
- Take an umbrella lest it should rain.(带把伞,以防下雨。)
表示愿望
| 引导词 | 示例 |
|---|---|
| wish + 与现在相反 | I wish I were taller.(但愿我能再高些。) |
| wish + 与过去相反 | I wish I had studied harder.(要是我当初更用功就好了。) |
| wish + 与将来相反 | I wish it would stop raining.(但愿雨能停。) |
| would rather + 与现在相反 | I would rather you stayed here.(我倒希望你留在这里。) |
| if only + 各种时间 | If only I were rich!(要是我富有就好了!) |
表示比较或方式
由 as if / as though 引导,谓语用 过去时态 或 had + 过去分词。
- He talks as if he knew everything.(他说起话来仿佛无所不知。)(与现在相反)
- She looks as if she had seen a ghost.(她看上去像是见了鬼。)(与过去相反)
It is (high) time that ...
句型 It is (high) time that ... 后的从句谓语用 过去时态 或 should + 动词原形,表示 「该做某事了」。
- It is high time that we left.(我们该走了。)
- It is time that you should go to bed.(你该去睡觉了。)