In grammar, the subjunctive mood (abbreviated or ) is a verb mood typically used in subordinate clauses to express a wish, emotion, possibility, judgment, opinion, necessity, or action that has not yet occurred. It is sometimes referred to as the conjunctive mood, as it often follows a conjunction. The details of subjunctive use vary from language to language.
there is a form of a different mood: be happy! – We are addressing second person but we do not use the form of the second person (are happy). With other verbs, it is not possible to illustrate this – they have lost the inflexions
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