Subjunctive mood

The subjunctive is a grammatical mood (that is, a way of speaking that allows people to express their attitude toward what they are saying) found in many languages. Subjunctive forms of verbs are typically used to express various states of unreality such as wish, emotion, possibility, judgment, opinion, obligation, or action that has not yet occurred; the precise situations in which they are used vary from language to language. The subjunctive is an irrealis mood (one that does not refer directly to what is necessarily real) – it is often contrasted with the indicative, which is a realis mood (used principally to indicate that something is a statement of fact).

Subjunctives occur most often, although not exclusively, in subordinate clauses, particularly that-clauses. Examples of the subjunctive in English are found in the sentences "I suggest that you be careful" and "It is important that she stay by your side." (The corresponding indicative forms of the verbs in bold would be are and stays.)

Subjunctive may be denoted by the abbreviation sjv or sbjv. It is sometimes referred to as the conjunctive mood, as it is mostly found in clauses introduced by a conjunction.

The Proto-Indo-European language, the reconstructed common ancestor of the Indo-European languages, had two closely related moods: the subjunctive and the optative. Many of its daughter languages combined or merged these moods.

In Indo-European, the subjunctive was formed by using the full ablaut grade of the root of the verb, and appending the thematic vowel *-e- or *-o- to the root stem, with the full, primary set of personal inflections. The subjunctive was the Indo-European irrealis, used for hypothetical or counterfactual situations.

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