a set of verb forms that would represent a denoted act or state not as fact but as contingent or possible or viewed emotionally (as with doubt or desire). The "would" in the last sentence makes its mood subjunctive.
A verb is in the subjunctive when it shows the content of a clause is being doubted, feared true etc. rather than being stated. See also indicative. For example: I'd think carefully about that if I were you. (Were is in the subjunctive.)
A form of sentence structure in English that is used to indicate statements that are known to be contrary to fact, wishes, or the like: "If I were rich, I could pay to have you killed. Instead, I will have to do it myself."