Page 270 - Practical English Usage 3ed - Michael Swan, Oxford

2 if ... was/were to
This is another way of talking about unreal or imaginary future events.
If the boss was/were to come in now, we'd be in real trouble.
(= If the boss came ...)
What would we do ifI was/were to lose myjob?
It can be used to make a suggestion sound less direct, and so more polite.
Ifyou were to move your chair a bit, we could all sit down.
This structure is not normally used with verbs like be or know, which refer to continuing situations.
IfIknewhername...(NOT 1ftwereteknewherMme...J For the difference between was and were after if. see 258.4.
3 if it was/were not for
This structure is used to say that one event or situation changes everything.
If it wasn't/weren't for his wife'S money he'd never be a director. (= Without his wife's money ...J
If it wasn't/weren't for the children, we could go skiing next week. To talk about the past we use If it had not been for.
Ifit hadn't been for your help, I don't know what I'd have done.
But for can be used to mean 'if it were not for' or 'if it had not been for'.
Butfor your help, I don't know what I'd have done.
4 leaving out if: conversational
Ifis sometimes left out at the beginning of a sentence in a conversational style, especially when the speaker is making conditions or threats.
You want to get in, you pay like everybody else. (= If you want ...) You touch me again, I'll kick your teeth in.
S leaving out if: formal inversion-structures
In formal and literary styles, ifcan be dropped and an auxiliary verb put before the subject. This happens mostly with were, had and should.
Were she my daughter, ... (= If she were my daughter ...J Had I realised what you intended, ... (= If I had realised ...J Should you change your mind, ... (= If you should change ...)
Negatives are not contracted.
Had we not missed the plane, we would all have been killed in the crash.
J
For other uses of inverted word order. see 302-303.
6 leaving out words after if
We sometimes leave out subject + be after if. Note the common fixed expressions ifnecessary, ifany, ifanything, ifever, ifin doubt.
I'll work late tonight ifnecessary. (= ... if it is necessary) There is littl£ ifany good evidence for flying saucers.
I'm not angry. If anything, I feel a littl£ surprised.
He seldom ifever travels abroad.
If in tUJubt, ask faT help. (= If you are in doubt ...J
"_..I' . ...1 (NOT llUUl'f t we rnfSseu ...
if (6): other points 261
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