The label imperative refers to the formal sentence type which has the following distinctive sentence pattern: Keep quiet!
This pattern commonly expresses a command. In English, an imperative usually doesn’t have a subject (though you is understood as its subject). In writing an imperative is often punctuated with an exclamation mark.
- Wash your hands!
- Get lost!
- Shut up!
- Don’t smoke in the kitchen!
It is possible, however, to put you into subject position, as in the following example: You do your homework.
Ideally, the label imperative should be reserved for sentences which have this form. However, in English it is possible to use an imperative sentence for a function other than giving a command. For example if you are going on a picnic I may say ‘Have a nice time‘. Although this sentence has the form of an imperative, it is not an order, only a hope.
Similarly it is possible to use another sentence form to give an order. For example an army officer is more likely to say ‘I order you to hold your position’ instead of ‘Hold your position’.
This is certainly an order, although it doesn’t have the form of an imperative sentence. Instead it has the form of a declarative sentence.