first conditional could modal
I'm trying to clarify why this sentence seems wrong:
If there is no strict definition, everyone could understand migration slightly differently.
My initial response was that it was wrong, but why? These sentences seem OK:
If he doesn't look at the map he could get lost.
If he doesn't do his work, he could get fired.
Are my intuitions wrong here? Is it actually OK? Is there some interference between could for ability and could for possibility?
Solution 1:
If there is no strict definition, everyone could understand migration slightly differently.
It's a bit awkward to parse. I think the key here is potential confusion on two separate points, creating a slew of parsing options.
Differently from what? Differently from one another, or differently from how they had previously understood. This is the big one since the tense and aspect used doesn't ever really resolve this. Understand can be stative or dynamic depending on what follows. And in this sentence, it can still be either static or dynamic after you've read the whole thing.
Is could permissive? seems not, but you can't really decide until you decide on how differently is to be interpreted. A lot of people would shy away from could if it wasn't permissive at all. Those people will be expecting understand to be dynamic.
The sense is that the initial state of no strict definition has been in place for a while, so the circumstances conducive to different understandings have also been in place for a while. So there's no reason for one's personal understanding to have changed.
One solution is to lock down understanding as a state and not an event.
If there is no strict definition, everyone's understanding of migration could differ slightly.
There is still a bit of a glitch in aspect though. The statement is probably trying to make the case that this is sort of a universal truth. Many dialects use be to get that across.
If there is no strict definition, everyone's understanding of migration could be slightly different.
So I wouldn't call it wrong as is, but some people will be led down the wrong path initially.
The other two sentences you list as comparisons treat the probibility of an event. They are unequivocally about a changing state. Nothing is actually changing in your first example.