Your original example is a 3rd conditional.Is it also correct if I use " If we didn't built the reservoir, there would be a terrible flood"? Thanks!
The version you suggest should be "If we didn't build the reservoir .
I agree with Sound Shift, although I suppose If we didn't build... is grammatically correct."If we didn't build the reservoir, there would be a terrible flood" seems unlikely to me.
If the reservoir does not exist: "If we don't build the reservoir, there will be a terrible flood."
You are narrating the story of how you planned to build a reservoir.Your listeners do not know if the thing was actually built and you do not want to tell them YET. So you say: if we didn't build, there would be...Thanks a lot. However, I'm still confused about the difference between "If we didn't built the reservoir, there would be a terrible flood"(first conditonal narrated in the past tense) and " If we hadn't built the reservoir, there would have been a terrible flood."(third conditional) . They mean the same to me. Do they mean differently?
So do I.I think your #8 is possible, too
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If we hadn't built the reservoir there would have been a terrible flood means you did build the reservoir.Thanks a lot. However, I'm still confused about the difference between "If we didn't built the reservoir, there would be a terrible flood"(first conditonal narrated in the past tense) and " If we hadn't built the reservoir, there would have been a terrible flood."(third conditional) . They mean the same to me. Do they mean different things?