Unreal past structures

English often uses a past verb form to talk about a situation that is not past at all. In I wish I knew the answer, the speaker means “I do not know it now”. The past form signals distance from reality: the situation is imagined, regretted or different from what the speaker wants.

The time reference still matters. Use a past simple form for an unreal present, and a past perfect for an earlier event you regret:

I wish the office were closer. (It is not close now.)
If only we had checked the address. (We did not check it before.)
I wish I had taken the earlier train. (I took a later one.)

If only usually sounds more emotional or urgent than I wish, but the verb patterns are the same. In more formal English, were is possible with every subject in unreal clauses: If the answer were clearer, we could decide. In informal speech, many people use was with I/he/she: I wish it was Friday already.

Wishing for a change, not a fact

Use wish + would when you want a situation or another person's repeated behaviour to change. It can communicate impatience:

I wish the neighbours would turn the music down.
If only the printer would work for once.
She wishes her team would reply more promptly.

This is different from a simple unreal state. I wish I knew the password means I do not know it. I wish the system would recognise my password expresses frustration with the system's behaviour. For an ability you do not have, use could: I wish I could stay longer, not usually I wish I would stay longer.

The less common regret patterns

I wish I had more time refers to the present; I wish I had had more time yesterday refers to the past. The double had is correct: the first forms the past perfect, and the second is the past participle of have.

For preferences, would rather changes form according to whose action is involved:

I’d rather wait here. (I do the waiting.)
I’d rather you waited here. (You do the waiting.)
I’d rather you had called first. (You did not call first.)

After I’d rather you, the past form describes a current or future preference; the past perfect refers to an earlier action. Do not add to: I’d rather you to wait.

It’s time we left means leaving is due now. It’s high time we did something adds urgency or criticism. Again, the past form expresses distance or impatience rather than past time.

When as if sounds unreal

After as if/as though, a past form can mark an impression that seems unlikely or false: He talks as if he owned the place (he probably does not). For an earlier imagined event, use past perfect: She looked as if she had seen a ghost. When the comparison seems plausible, ordinary tense is also possible: It looks as if it is going to rain.

The central question is therefore not simply “Which tense happened first?” Ask whether the speaker presents the situation as real, desired, regretted or remote. That choice determines whether the past form marks time or distance.

Choosing between wish, if only and would rather

The verb after wish depends on the kind of difference between reality and desire. For a current state, use a past simple: I wish the office were closer. For a past event, use past perfect: I wish we had booked earlier. For behaviour you want to change, use would: I wish the delivery company would give a more accurate time window.

That last pattern often implies frustration, especially when the subject is another person or an external situation. It is less suitable for a state the speaker simply lacks: I wish I could drive describes ability; I wish I would drive normally suggests a choice or willingness to drive, not ability. If you want to change your own habit, I wish I would stop checking my phone is possible, but I wish I could stop or I wish I stopped may be more idiomatic depending on the meaning.

Would rather expresses preference rather than regret:

I’d rather take the train. (my action)
I’d rather you took the train. (your action, now or later)
I’d rather you had taken the train. (your earlier action)

The subordinate past form in the second example is not past time. It marks distance from reality, much like I’d rather you were here. With it’s time, the same distancing appears: It’s time we left means “we should leave now”; It’s about time the council repaired the bridge can sound critical.

Imagined conditions and what you cannot change

If it were not for the new grant, the project would close describes a present dependency. If it had not been for the grant, the project would have closed looks back at a past rescue. These are often shortened with were it not for and had it not been for in formal writing.

For something irreversible, past perfect after wish is the usual regret: If only I had saved the original file. For a situation still open to change, use a present or future-oriented form: I wish the office would extend its opening hours. Distinguishing regret from a desired change prevents wish + would from becoming a universal substitute.

Sources

• Cambridge Dictionary: Wish
• Cambridge Dictionary: Would rather, would sooner