Editing Conditional sentence (section)

==Crosslinguistic variation==

Languages have different rules concerning the [[grammar|grammatical]] structure of conditional sentences. These may concern the [[syntax|syntactic]] structure of the antecedent and consequent clauses, as well as the forms of verbs used in them (particularly their [[grammatical tense|tense]] and [[grammatical mood|mood]]). Rules for English and certain other languages are described below; more information can be found in the articles on the grammars of individual languages. (Some languages are also described in the article on the [[conditional mood]].)

===Latin===
{{main|Latin conditional clauses}}
Conditional sentences in [[Latin]] are traditionally classified into three categories, based on grammatical structure.

*simple conditions (factual or logical implications)
**present tense [if ''present indicative'' then ''indicative'']
:::{{lang|la|sī valēs, gaudeo}} "if you are well, I am glad"
:*past tense [if ''perfect indicative'' then ''indicative'']
:::{{lang|la|sī peccāvī, īnsciēns fēcī}} "if I did wrong, I did so unwittingly"
:*2nd person generalisations [if ''present or perfect subjunctive'' then ''indicative'']
:::{{lang|la|memoria minuitur, nisi eam exerceās}} "memory gets weaker, if you don't exercise it"

*future conditions
**"future more vivid" [if ''future or future perfect indicative'' then ''future indicative'']
:::{{lang|la|haec sī attulerīs, cēnābis bene}} "if you bring (literally "will have brought") these things, you will dine well"
:*"future less vivid" [if ''present or perfect subjunctive'' then ''present subjunctive'']
:::{{lang|la|sī negem, mentiar}} "if I were to deny it, I would be lying"

*counterfactual conditions
**"present contrary-to-fact" [if ''imperfect subjunctive'' then ''imperfect subjunctive'']
:::{{lang|la|scrīberem plūra, sī Rōmae essēs}} "I would write more, if you were in Rome"
:*"past contrary-to-fact" [if ''pluperfect subjunctive'' then ''pluperfect subjunctive'']
:::{{lang|la|sī Rōmae fuissem, tē vīdissem}} "if I had been in Rome, I would have seen you"

===French===
In [[French language|French]], the conjunction corresponding to "if" is ''si''. The use of tenses is quite similar to English:
*In implicative conditional sentences, the present tense (or other appropriate tense, mood, etc.) is used in both clauses.
*In predictive conditional sentences, the future tense or imperative generally appears in the main clause, but the condition clause is formed with the present tense (as in English). This contrasts with subordinate clauses introduced by certain other conjunctions, such as ''quand'' ("when"), where French uses the future (while English has the present).
*In counterfactual conditional sentences, the [[imperfect]] is used to express the condition (where English similarly uses the past tense). The main clause contains the [[conditional mood]] (e.g. ''j'arriverais'', "I would arrive").
*In counterfactual conditional sentences with a past time frame, the condition is expressed using the [[pluperfect]] e.g. (''s'il avait attendu'', "if he had waited"), and the consequence with the [[conditional perfect]] (e.g. ''je l'aurais vu'', "I would have seen him"). Again these verb forms parallel those used in English.

As in English, certain mixtures and variations of these patterns are possible. See also [[French verbs]].

===Italian===
[[Italian language|Italian]] uses the following patterns (the equivalent of "if" is ''se''):
*Present tense (or other as appropriate) in both parts of an implicative conditional.
*Future tense in both parts of a predictive conditional sentence (the future is not replaced with the present in condition clauses as in English or French).
*In a counterfactual conditional, the imperfect [[subjunctive]] is used for the condition, and the [[conditional mood]] for the main clause. A more informal equivalent is to use the imperfect indicative in both parts.
*In a counterfactual conditional with past time frame, the pluperfect subjunctive is used for the condition, and the past conditional (conditional perfect) for the main clause.

See also [[Italian verbs]].

===Slavic languages===
In [[Slavic languages]], such as [[Russian language|Russian]], clauses in conditional sentences generally appear in their natural tense (future tense for future reference, etc.) However, for counterfactuals, a conditional/subjunctive marker such as the Russian бы (''by'') generally appears in both condition and consequent clauses, and this normally accompanies the past tense form of the verb.

See [[Russian grammar]], [[Bulgarian grammar]], etc. for more detail.