Unit 34. If sentences (present / future)

A.
Compare these examples:

Tom: I think I left my lighter at your house. Have you seen it? Ann: No, but I’ll look. If I find it, I’ll give it to you.

—-

In this example there is a real possibility that Ann will find the lighter. So she says: “If I find… I’ll…” (see also Unit 9c).

—-

Ann: If I found a $100 bill on the street, I would keep it.

—-

This is a different type of situation. Ann is not thinking about a real possibility; she is imagining the situation. So she says: “If I found… I would…” (not “If I find … I’ll … “).

When you imagine a future happening like this, you use a past tense form (did/came/found, etc.) after if. But the meaning is not past:

What would you do if you won a million dollars?

If we didn’t go to their party next week, they would be very angry.

Ann wouldn’t lend me any money if I asked her.

B.
We do not normally use would in the if part of the sentence:

I’d be very frightened if someone pointed a gun at me. (not if someone would point)

If we didn’t go to their party next week, they would be angry, (not if we wouldn’t go)

Sometimes it is possible to say if… would, especially when you ask someone to do something in a formal way:

I would be very grateful if you would send me your brochure and price list as soon as possible, (from a formal letter)

C.
In the other part of the sentence (not the if part) we use would/wouldn’t. Would is often shortened to ‘d, especially in spoken English:

If you stopped smoking, you’d probably feel healthier.

They wouldn’t come to the party if you invited them. You can also use could and might:

They might be angry if I didn’t visit them. (= perhaps they would be)

If it stopped raining, we could go out. (= we would be able to go out)

D.
Do not use when in sentences like the ones in this unit:

Tom would be angry if I didn’t visit him. (not when I didn’t visit)

What would you do if you were bitten by a snake? (not when you were) See also Unit 9c.

For if sentences see also Units 35 and 36.