- Subjunctive contrary to present fact:
If + did / were + …, … would/ should/ could/ might + do (base form of the verb)
If I were you, I would go abroad at once. (I am not you.)
If he knew it now, he could help me. (He doesn’t know it now.)
- Subjunctive contrary to past fact:
If + had done + …, … would (might) have done …
If I had known your telephone number yesterday, I would have phoned you. (I didn’t know your telephone number.)
If you had come here a little earlier just now, you might have met her. (You didn’t come here earlier.)
- Subjunctive contrary to future fact:
(1) If + should + v., … would + v. (very unlikely) (translated as "in case")
If it should rain tomorrow, you could stay at home.
If I should fail, what should Ido?
(2) If + did / were to + v …, would + v. (completely impossible)
If the sun were to rise in the west, I would lend you the money.
If you finished it in 3 minutes, I would give you my car.
- Special key points
[Simple memory aids]:
● The "object clause" after the following verbs uses the subjunctive, i.e. should + base form of the verb; should is omitted in American English (a TOEFL grammar point). Common verbs of this kind include: order, ask, decide, demand, require, recommend, suggest, insist (to firmly demand), advise, etc.
He suggested that we (should) help them with English.
The teacher ordered that the homework (should) be finished within half an hour.
● The appositive clause after the following nouns uses the subjunctive "should + base form of the verb" (should can be omitted). Common nouns of this kind include: suggestion, order, request, demand, importance, proposal.
He made a suggestion that we (should) have a fancy dress party.
I think it is a thing of importance that it (should) be done soon.
● It is / was important / necessary / natural / essential / advisable / strange / surprising, etc. + that + subject + should + v.
It is strange that you should say such a thing.
It was important that you should tell me all the information.
● In the object clause after wish and in the adverbial clause after as if, the following subjunctive forms must be used:
subject + wish + (that) + subject + did / were (for the present)
had done (for the past)
would + v. (for the future)
I wish that I met my uncle now.
I wish I had met my uncle yesterday.
I wish I could meet my uncle tomorrow.
● It is (high) time that … + did / were …
It is time that you went to bed.
● would rather that … + did / were …
I would rather that you were not here now.
● would sooner that … + did / were …
I would sooner that you got up earlier.
I would sooner that you were not my brother.