Some verbs of command, desire or suggestion require a verb in a subordinate clause to be in the subjunctive. The subjunctive mood (sometimes referred to as the conjunctive mood) is a grammatical mood of the verb that expresses wishes, commands, emotion, possibility, judgment, and necessity. It's used to express hypothetical or contrary to fact situations.
It is important to note that the time reference of the sentence is conveyed by the tense of the main verb rather than the subjunctive. Thus the following main verb refers to the present (with possible relevance to the future):
The following main verb refers to the past (with possible relevance to the present):
- I wish that Susan were here.
The terms present subjunctive (be) and past subjunctive (were) can be misleading, as they describe forms rather than meanings: the past and present subjunctives are so called because they resemble the past and present indicatives, respectively, but the difference between them is a modal one, not a temporal one.
- I wishedthat Susan were here.
For example, in "I asked that it be done yesterday," be done (a present subjunctive) has no present-tense sense; and likewise, in "If that were true, I'd know it," were (a past subjunctive) has no past-tense sense.
The past subjunctive is used after the conjunction if in a contrary-to-fact protasis. For example:
In many dialects of English, the indicative (was) can take the place of the subjunctive (were), although this is sometimes considered erroneous in formal or educated speech and writing.
- If I were a millionaire, ...
- If I were a rich man, ...
- If I was a millionaire...
- If he was a rich man...
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