The subjunctive is used to express conjecture, uncertainty, emotional response, subjectivity, doubt, probability, influence, the yet unknown, and that which one would like to have happen. Often the subjunctive is used in a sentence of two or more clauses. The verb in the main clause determines whether the verb in the dependent clause is subjunctive or indicative.
Dependent clauses introduced by the following conjunctions sometimes require the subjunctive .
Subjunctive is used when future or pending actions are implied or expressed.