The subjunctive is a verb mood used to express situations that are not presented as simple facts. It often marks wishes, demands, recommendations, necessities, hypotheticals, or conditions that are uncertain or contrary to reality. In English, the subjunctive is mostly visible in certain fixed patterns rather than in many distinct verb endings. You recognize it by the type of meaning and by a few key forms like the base verb after “that” and “were” in unreal statements.

Tense locates a verb in time, while mood shows the speaker’s attitude toward the action or situation. The subjunctive contrasts with the indicative, which presents statements as facts or questions about facts. It also contrasts with the imperative, which directly gives commands. Understanding subjunctive meaning first helps you choose the right structure even when the verb form looks similar to other moods.

After certain verbs, adjectives, and nouns that express demands, recommendations, or necessity, English often uses a “that-clause” with the base form of the verb. This is called the mandative subjunctive. The verb in the that-clause does not take -s in the third person singular and does not show past tense, because it expresses what should happen, not what is happening. This structure is common in formal writing and careful speech.

Rule	🇨🇳 中文 规则	Example	🇨🇳 中文 示例
Use base verb after that when expressing demand or recommendation	✅ 在表达要求或建议时，that 之后使用动词原形	They insisted that he leave now.	✅ 他们坚持让他现在离开。
No third person singular -s in the that-clause	✅ that 从句中没有第三人称单数 -s	She recommends that he study more.	✅ 她建议他多学习。
Use be as be for all subjects	✅ 对所有主语使用 be 的原形形式	It is essential that I be present.	✅ 我必须在场。
Often follows verbs like demand, insist, suggest, recommend, propose, require	✅ 常跟随在诸如 demand、insist、suggest、recommend、propose、require 这类动词之后	The coach suggested that she rest.	✅ 教练建议她休息。
Also follows adjectives like important, essential, vital, necessary, crucial	✅ 也跟在像 important、essential、vital、necessary、crucial 这样的形容词之后	It is vital that we act quickly.	✅ 我们必须迅速行动，这一点至关重要。

English has common alternatives to the mandative subjunctive, especially in everyday style. You can often replace it with “should” plus the base verb, or sometimes with an infinitive construction. These alternatives keep the same meaning of recommendation or necessity, but they change the tone and formality. Choosing between them is mostly a style choice unless a specific register is expected.

Rule	🇨🇳 中文 规则	Example	🇨🇳 中文 示例
Use should to soften or for common everyday phrasing	✅ 使用 should 来缓和语气或用于日常常见表达	They insisted that he should leave now.	✅ 他们坚持说他现在应该离开。
Use an infinitive when the subject is the same or can be framed that way	✅ 当主语相同或可用同样的结构来表达时，使用不定式	She wants him to study more.	✅ 她希望他多学习。
Keep meaning of necessity even when the form changes	✅ 即使形式改变，仍保持必要性的含义	It is important that we be on time.	✅ 我们准时到达很重要。

In unreal or counterfactual statements, English often uses “were” with I, he, she, and it. This form signals that the situation is imagined, unlikely, or contrary to reality. It commonly appears after “if” and after “wish,” and it is especially expected in formal English. In informal speech, many speakers use “was,” but “were” clearly marks the subjunctive meaning.

Rule	🇨🇳 中文 规则	Example	🇨🇳 中文 示例
Use were for unreal condition with I, he, she, it	✅ 对 I、he、she、it 的非现实条件使用 were	If I were taller, I would play basketball.	✅ 如果我更高，我会打篮球。
Use were after wish for present unreal situations	✅ 在对现在的非现实情形的愿望中使用 were	I wish she were here.	✅ 我希望她在这里。
Use were after as if or as though for unreal comparisons	✅ 在 as if 或 as though 之后用于非现实比较	He acts as if he were the boss.	✅ 他好像是老板。
Was is common informally, were is more standard for unreality	✅ 口语中常用 was，在非现实情形下，were 更为标准	If I was late, it was my fault.	✅ 如果我没有那么累，我就会留下来。

Subjunctive meaning often appears in conditional sentences that describe unreal or hypothetical situations. The form you choose depends on whether the condition is open and possible, or unreal and contrary to fact. Unreal present conditions typically use past form with “would” in the result, and unreal past conditions use past perfect with “would have.” This is sometimes called the “past subjunctive” and “perfect subjunctive” in descriptions of English usage.

Rule	🇨🇳 中文 规则	Example	🇨🇳 中文 示例
Open condition uses present tense forms, not subjunctive meaning	✅ 开放条件使用现在时形式，而非虚拟语气含义	If it rains, we will stay inside.	✅ If it rains, we will stay inside。
Unreal present uses past form and would in the result	✅ 非现实的现在使用过去形式和 would 在结果中	If it rained, we would stay inside.	✅ If it rained, we would stay inside。
Unreal present with be often uses were	✅ 含 be 的非现实现在常用 were	If she were ready, we would leave.	✅ If she were ready, we would leave。
Unreal past uses past perfect and would have	✅ 非现实的过去使用过去完成时和 would have	If I had known, I would have called.	✅ If I had known, I would have called。

After “wish,” English uses forms that emphasize unreality rather than actual time. For present wishes about now, English often uses past forms, and with be it commonly uses “were.” For wishes about the past, English uses past perfect to show regret about something that did not happen. For wishes about the future, English typically uses “would” to express a desire for change, often involving someone else’s behavior.

Rule	🇨🇳 中文 规则	Example	🇨🇳 中文 示例
Present wish uses past form for unreality	✅ 现在愿望使用过去式以表达非现实	I wish I had more time.	✅ 我希望我有更多时间。
With be, present wish often uses were	✅ 对于现在的愿望，使用 be 时通常用 were	She wishes she were taller.	✅ 她希望自己更高。
Past wish uses past perfect for regret	✅ 对过去的愿望使用过去完成时以表达遗憾	I wish I had studied earlier.	✅ 我希望我能更早学习。
Future wish often uses would for change in behavior or situation	✅ 对未来的愿望通常使用 would 来表示行为或情境的改变	I wish he would stop interrupting.	✅ 我希望他不要再打断我。

English keeps the subjunctive in several fixed phrases that are common in formal speech, writing, or ceremonial contexts. These expressions often use the base verb or an older pattern and may not follow everyday grammar expectations. Learning them as chunks helps you recognize subjunctive meaning even when the structure feels unusual. They are not interchangeable with indicative forms in many contexts because the phrase itself has become conventional.

Word/Phrase	🇨🇳 中文 单词/短语	Definition	🇨🇳 中文 定义	Example	🇨🇳 中文 示例
God save	✅ 神保佑	an expression of a wish	✅ 一个表达愿望的短语	God save the King.	✅ 愿上帝保佑国王。
Long live	✅ 长久地	a wish for long duration or success	✅ 对长久持续或成功的愿望	Long live the republic.	✅ 共和国万岁。
Be that as it may	✅ 尽管如此	despite that fact or argument	✅ 尽管存在这一事实或论点	Be that as it may, we must decide.	✅ 尽管如此，我们必须决定。
Suffice it to say	✅ 只需说	it is enough to say	✅ 只需要说	Suffice it to say, I disagreed.	✅ 只需说，我不同意。
So be it	✅ 就这样吧	acceptance of a decision or outcome	✅ 对某一决定或结果的接受	If that is your choice, so be it.	✅ 如果那是你的选择，那就这样吧。

In mandative subjunctive clauses, the verb stays in the base form, and negation is formed with “not” before the base verb. English does not use do-support inside the mandative subjunctive, so you do not say “does not leave” in that specific structure. In unreal “were” patterns, negation works normally with “not,” and contractions are possible. Paying attention to where “not” goes helps keep the structure clearly subjunctive.

Rule	🇨🇳 中文 规则	Example	🇨🇳 中文 示例
Mandative negative uses not plus base verb	✅ 强制性否定使用 not 加基本动词	They demanded that he not speak.	✅ 他们要求他不得说话。
Avoid does not in mandative subjunctive	✅ 避免在强制性虚拟语气中使用 does not	It is important that she not miss the meeting.	✅ 重要的是她不要错过会议。
Were patterns negate with not as usual	✅ 使用 were 的句型通常与 not 搭配表示否定	If I were not busy, I would go.	✅ 如果我没有那么忙，我就会去。
Contractions are possible in speech and informal writing	✅ 口语和非正式写作中可以使用缩写	If he weren’t so tired, he would stay.	✅ 如果他没有那么累，他就会留下来。

Subjunctive choices in English are closely tied to register and clarity of meaning. The mandative subjunctive is common in American English and in formal legal or academic style, while British English often prefers “should” in similar contexts. Using “were” for unreality is more formal and explicit than using “was,” especially with I and he she it. The key is to match form to meaning: use subjunctive patterns when you want to highlight demand, necessity, or counterfactuality.

Region	🇨🇳 中文 地区	Word	🇨🇳 中文 单词	Regional Definition	🇨🇳 中文 区域定义
American English	✅ 美国英语	that he leave	✅ that he leave	common formal and neutral mandative subjunctive	✅ 常见的正式且中性的 mandative subjunctive 表达
British English	✅ 英国英语	that he should leave	✅ that he should leave	common alternative to mandative subjunctive	✅ 对 mandative subjunctive 的常见替代表达
Formal style	✅ 正式风格	If I were	✅ If I were	preferred marker of counterfactual meaning	✅ 反事实含义的首选标记
Informal style	✅ 口语风格	If I was	✅ If I was	common speech variant, less explicit counterfactual marker	✅ 口语变体，反事实标记不那么明显