Subjunctive is a special rare verb in English. The structure is extremely simple:
- be (past) - I were, you were, he/ she/it were, we were, they were
- be (present) - I be, you be, he/ she/ it be, we be, they be
- all other verbs (past & present) - I play, you play, he/ she/it play, we play, they play
The subjunctive is typically used after 3 structures:
- the verbs: ask, command, demand, insist, propose, recommend, request, suggest + that
- the nouns: demand, recommendation, insistence, request, preference, request, proposal, suggestion
- the expressions: it is desirable, essential, important, necessary, imperative, vital + that
Some links:
gmat