@ ENAFEX
Subjunctive mood sentences are special types of sentences, which violate the normal rules applied to subject verb agreements in number and tense but are still considered grammatical.
The command subjunctive mood of the verb indicates a desire, intention, command, recommendation, request, resolution, or advice, used along with such adjectives as advisable, better, desirable, and directive, essential, fitting, imperative, important, necessary, urgent and vital. Important to note here is the word - that - It will always accompany such command subjunctive mood sentences and the verb of the relative sentences will always be the base or root form of the verb.
There are subjunctive mood uses in the present tense and the past tense. In the command subjunctive, the verb is always in the base form or imperative form (looking like a plural present tense verb), even if the subject is plural and the tense is past or future. Sentences in which one would use such verbs as is, are, was, were or will be , should use the root verb - be -, in the case of the command subjunctive.