Is a conditional sentence in the form of "If + a past tense (simple, perfect, ...)+, there was + something." grammatical?

Question

I know the basic rules and structure of second and third and mixed conditionals. I know that in the main clause of them we should use would, could, or might.

But I have come across this sentence in a text which is written by a non-native (but expert in English) writer and I suspect whether it is a grammatical error or it is an other structure of conditional that I do not know.

If I had passed the previous exam, there was no need to retake it.

Is it correct?

I think it is better (or the only correct way) to say:

If I had passed the previous exam, there would be no need to retake it.

Answer 1

Grammatical, yes. But does it have the meaning you want? Unclear.

The original sentence there is a real conditional with a past perfect condition clause, and a simple past result clause, which is fine. The meaning is a bit odd, but it can apply. For instance, let's say I take an exam, then a teacher tells me to take the exam again, so I do. Then I hear that I might have passed the first one. In that context, it makes sense to reflect on the situation and say, "If I had passed the previous exam, there was no need to retake it. Oh well."

Your second sentence is an unreal conditional with a conditional clause in the simple past time, and a result clause in the present. It roughly means, "I did not pass the previous exam, so now I have to retake it."

Answer 2

Here's what I would write:

Since I passed the previous exam, there was no need to retake it.

I would not use a conditional there as there is no condition in the idea.

VERSUS 1) or 2) or 3)

1. If I had passed the previous exam, there wouldn't be a need to retake it.
   Talking about the past. He flunked it. He needs to retake it at some point in the present.
2. If I had passed the previous exam, there wouldn't have been a need to retake it. Talking about the past, he already retook it.

For me if signals a conditional of one kind or another, and I don't think that first sentence requires it.

Also, if the guy doesn't know if he passed if or not, he can use the following:

3. If I passed the exam, there would be no need to retake it.
   Talking in the present time. He doesn't know if he passed it or not.