'If only I ___ a little more, I ____ to help you'
1) knew, might be able
2) had known, may be able
3) had to know, might be able
4) knew, might have been able
I'd choose the first one, is that right?
I would really appreciate your help.
I know the question isn't alive still for Marseillais, but it has me intrigued. I'll try to explain:
The correct straightforward sequence of tenses in conditionals is as follows (if-clause/main-clause): 1st. Present/Future; 2nd. Simple past/Conditional. 3rd. Past perfect/Past conditional.
What are the tense sequences being offered?
1) knew, might be able (
Simple past/Conditional)
2nd.
2) had known, may be able
(Past perfect/Present)
3) had to know, might be able
(Simple past/Conditional)
2nd.
4) knew, might have been able
(Simple past/Past conditional)
at first sight, but there is a mixed conditional with this form which relates ongoing circumstances (
if I knew) to a past event (
I might have been able), but it's more common with negative conditions
(if I didn't know, I would not have...) I think it's this that has made people accept 4 and also explains their reluctance to do so. The form is odd with a positive condition.
What interests me particularly is why have so many people, except I think for Hermione, rejected the perfectly correct 3. What is so very odd about
3. If only I had to know a little more, I might be able to help ?
I think it's just very hard to think of circumstances where it might apply. Change it a bit,
If only I had to drive the car, I might be able to pass the test, and the grammatical correctness becomes clear, I'd say.