# Different conditional clauses — “if you saw”, “if you were to see”, “if you had seen”

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).

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?

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Both of those sentences are related to hypothetical situations. – Phonics The Hedgehog Aug 10 '12 at 19:46
The last point has been addressed in this dedicated question: “Would have” in conditional clauses. – RegDwigнt Oct 29 '13 at 10:00
“It is clear that a division of conditionals into the zero, first, second, and third categories does not adequately reflect actual usage.” —from “If only it were true: the problem with the four conditionals”, Christian Jones and Daniel Waller, ELT Journal 65:1 pp 24–32 (2011), Oxford University Press, doi: 10.1093/elt/ccp101. – tchrist Jan 24 '15 at 14:30

There is no difference in meaning between your first two examples. However, the construction with were to see is more formal and slightly antiquated.

However, there is a difference between your second two examples, namely that this one is not grammatically correct:

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

In English we don't use the modal verb would in the if-clause of a condition of this sort. This condition must be phrased as in your other example:

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

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I don't quite see it that way; see my answer. – tchrist Aug 10 '12 at 20:38
In this sentence "If you had seen a lion in a thick forest, what would have you done?", the indefinite article `a` is likely to be replaced with the definite article `the`. Am I right? You're a native English speaker living in United States as your profile indicates and can easily see what is incorrect. There are no articles at all in my native language therefore, it's quite difficult to see which article is applied where. – Tiny Aug 11 '12 at 0:34
@Tiny: As a native English speaker myself, if you replace a lion with the lion the question has changed from one where you're just referring to a generic lion that might or might not exist to a specific lion—perhaps one you yourself had seen and you were wondering what your listener would have done in that situation. The original sentence (with a lion) can stand alone. Change it to the lion and you should've already mentioned the specific lion in a prior sentence. – Ben Hocking Aug 11 '12 at 1:58
When "will" is used with the "if" clause? - (1) If you will/would kindly lend me your book, I will be thankful to you. (2) If you will not/would not mind lending me your book, I will be thankful to you. (3) If you will/would wait a while, I will check it for you. Are these sentences correct? Could you please tell me? – Tiny Oct 26 '12 at 20:50
@Tiny I think you had best make that a new question. – tchrist Oct 26 '12 at 20:52

There is no difference in meaning between the first two sentences:

• 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?

Your third sentence is also grammatical, but means something slightly different:

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

The difference is that the first pair are talking about a hypothetical situation in the future, so something that has not yet occurred, while the third is talking about a hypothetical situation in the past, that is, one construed to have already occurred.

Your fourth sentence is not grammatical in English:

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

It's not grammatical because in English the protasis (the first part) of a conditional must not itself be in the conditional; that mood-like sense is reserved for the apodosis, the second part, and only when the protasis is in the past. There are many other conditional constructs in English beyond this one, but "If X would ..., then Y would ..." is not one of them. Native speakers of German sometimes try to use this sequence when first learning English, but it is not valid in English.

In contrast to JSBձոգչ's answer, I don't myself find the were to version as more formal, nor period-limited. Instead, I just see it as wordier than need be. Please note that I am not saying he's wrong, just that I do not share his view. Native speakers often differ on things like this, depending on their own experiences.

One arguable advantage with the were to construct is it does allow for expansion to make things come across as more tentative if desired. For example, If you were to happen to see ... The construction I see as slightly antiquated is If you should see, or its extension If you should happen to see...

A second arguable advantage with the were to construct might be that it somewhat emphasizes the subjunctive / hypothetical aspect of the protasis. That's because were is the last morphological vestige of the Old English past subjunctive that remains in Modern English, and even here is distinguished from the past indicative in only the first and third persons singular.

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Actually, there is a difference between the first two. They mean the same, but in that the second sentence (with "were") is in the pure subjunctive, the first clause always implies a hypothetical situation. The other, "if you saw a lion, ..." can be finished in two ways.

If you saw a lion in the thick forest, what would you do?

If you saw a lion in the thick forest, why didn't you tell someone sooner?

The first is hypothetical, but the second questions a past event. On the other hand,

If you were to see a lion in the thick forest, why didn't you tell someone sooner?

is simply nonsense. Thus, the pure subjunctive is preferred by some native speakers due to its unambiguity.

Note, however, that because it is no longer common, this may be seen by some to indicate hauteure.

The second pair of sentences you understand correctly. The formulation you give may be the literal translation from the subjunctive of your native language, but [reference needed: I will try to find one] this form of the subjunctive has passed out of usage in lieu of the simpler "had seen," which is the current proper subjunctive use in the past tense.

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Your alternate sequence of tense (past indicative, past indicative) is certainly valid, but it isn't what he's asking. The big problem is pretending that "if you were to" is more subjunctive than "if you saw". It isn't. Furthermore, his failed sequence of tenses is not "a translation from the subjunctive"!! Go read The Owl and the Nightingale for real subjunctive uses. – tchrist Aug 10 '12 at 21:04
Of course it is not "more subjunctive"! I did not say it was. It is simply always subjunctive in the same tense. "If you saw" is subjunctive, but is also past tense conditional. – shipr Aug 10 '12 at 21:09
"See" is present tense; "saw" is past tense. Check your dictionary. – tchrist Aug 10 '12 at 21:10
The second pair of sentences is translated into the English from the subjunctive of the source language, but incorrectly. Therefore IT IS a translation from the subjunctive. Perhaps you should think before you reply? And so why the downvote? – shipr Aug 10 '12 at 21:11
Provide the source language. I disbelieve. This is likely mistranslation of the word subjunctive. – tchrist Aug 10 '12 at 21:19