Given the following sentences, what is the difference between the conditional clauses in them? 

> * If you **saw** a lion in a thick forest, what would you do?
* If you **were to see** a lion in a thick forest, what would you do?

I'm asking this simple thing because it's confusing me, since there is no such thing in my native language (it's quite different from English).

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I can understand this one (it may be a different question):

> If you **had seen** a lion in a thick forest, what **would have** you **done**?

but it's a bit confusing me. In my native language, it's always formulated as follows:

> If you **would have seen** a lion in a thick forest, what would have you done?

Does this make any difference in English?