Inversion

Marcela asks:

A very specific question, about grammar. Is there a rule about 'inverted subject verb word order in conditionals?’

 Martin Parrott answers:

Yes there is. It sounds terribly complicated - but really there are three examples when you can, kind of, invert the subject and the verb, and it's easy to learn them - but they're not terribly common.

Example 1: Future

The first case is a conditional referring to the future. You might say, if it rains, I'll stay at home. But, there is an alternative to that. Instead of saying 'if it rains', you can say 'should it rain'. Now there you're inverting, if you like, the verb should (it's an auxiliary verb) and the subject - inverting the order. That's for conditionals for the future: ‘should it rain I'll stay at home’, ‘should it be fine, I'll go out’. It's a little bit unusual, and it's a little bit formal.

Example 2: Present

There are two more phrases which involve some degree of inverting (changing round the subject and the verb). There's also what we sometimes call the second conditional: they are conditionals where we're talking about the present and imagining it's the present. It's different in some ways - so ‘I've got a friend who's really healthy and well and doesn't need looking after, but if he were ill, I'd look after him’.

We have another conditional which is sometimes called the second conditional - which we use to refer to things in the present when we imagine if they were different. So for example: ‘I've got a friend who's really healthy, never ill, never needs looking after’, but [I might imagine it!] if he were ill, what would I do? ‘If he were ill, I'd look after him.’ Now there is another way of saying that, which is ‘were he ill, I'd look after him’ - and there, we'd invert the auxiliary verb and the subject. So, instead of ‘he were ill’ we changed it to ‘were he ill’ and we leave off the 'if'.

So that's our second example. Of course, that's quite an interesting one too, because we're using 'were' instead of 'was' and remember in sentences like this where we're talking about the present and we're imagining it different (our second conditional sentences), we can use 'were' instead of 'was' after the subject. We can't say ‘was he ill, I'd look after him’ - it's the 'were' here.  ‘Were he ill, I'd look after him’, ‘were he miserable, I would try and cheer him up’, ‘were he poor, I'd give him presents’.

Example 3: Conditional to talk about the past

Normally if we're talking about the past and imagining if things were different, we use ‘if’ and then we use what we call the past perfect tense. So, ‘if I had known he was tired, I would have gone home earlier’ (I stayed there all night talking to him; I didn't know he was tired). If I'd known - I had known - he was tired, I would have gone home earlier.

There's an alternative to that we can use. Instead of saying ‘if I had known’, we can say ‘had I known’. We invert the 'had', the auxiliary verb and the subject – so our alternative to ‘if I had known’ is ‘had I known’. ‘If I had seen him, I would have spoken to him’ – ‘had I seen him I would have spoken to him’. ‘If she had got the job, she would have been happier’ – ‘had she got the job, she would have been happier’.

All the same

The interesting thing about these three examples is, in a way they’re all the same. In each of these examples, we get rid of ‘if’ and then we invert (we change the order of) the auxiliary verb and the subject. And each of them is more formal than using ‘if’, and each of them suggests that the condition – that this ‘if’ clause, the condition – is a bit less probable.