Mood is a grammatical category which indicates the attitude of the speaker towards the action expressed by the verb from the point of view of its reality
Three: the indicative mood, the imperative mood and the subjunctive mood
The indicative mood shows that the action or state expressed by the verb is presented as a fact
The indicative mood is also used to express a real condition, i. e. a condition the realization of which is considered possible
The imperative mood expresses a command or a request
In modern English the imperative mood has only one form, which coincides with the infinitive without the particle "to"
It is used in the second person (singular and plural)
In forming the negative the auxiliary verb "to do" is always used, even with the verb "to be"
The auxiliary verb "to do" may also be used in affirmative sentences to make the request more emphatic