Forms of a sentence

There are four forms of a sentence:

A statement: That hotel restaurant serves a buffet breakfast.

A question: Do you expect me to believe what you just said?

A command: Don't just stand there. Do something.

An exclamation: What a terrible waste of time.

The four forms of a sentence correspond to the four basic sentence functions that follow.


Functions of sentences
There are four types of functions performed by sentences:  declarative, interrogative, imperative, or exclamatory.



A declarative sentence makes a declaration or statement which is contrast to a command, a question, or an exclamation. This is the most common type of sentences. The subject comes the verb in a declarative sentence which always ends in a full stop/period.
My parents like to watch bullfights.
She said I don’t love dogs as much as she does.


An interrogative sentence asks a question and ends in a question mark. This distinguishes it from the other types of sentences – declarative, imperative, and exclamatory – by the inversion of the normal subject-verb order with the verb or verb phrase coming before the subject.


Is a smoker like you able to do that – blow smoke rings?
(The auxiliary verb appears before the subject.)
Who is coming along with us to the haunted castle tonight?
(One of the question words [who, what, where, when, why, and how] who is used here to ask a question as the subject is unknown. The question word who does not invert with the auxiliary verb is.)
Is there enough money for us to dine in that restaurant?
(In this yes/no question which is answered with either yes or no, the auxiliary verb is inverted with the subject.)


An imperative sentence gives an instruction, expresses a command or issue a request. The subject is not normally shown in an imperative sentence, while the verb used is always in the base form; that is, a verb without any endings such as –s, -ed or -ing: Stop here! / Not: Stopped here! The implied subject is understood to be you. Imperative sentences vary in length; they can be as short as a single word: Look! An imperative sentence ends with a full stop/period or an exclamation mark. 

Bake it in the oven until golden brown. (Instruction)
Make a full report of the situation to your superior before the end of the week. (Command)
Please get me a carton of frozen yogurt on your way home. (Request)
Will you kids stop shouting. (Question phrased as a request)

An exclamatory sentence is not unlike a declarative sentence conveying strong feeling such as excitement, surprise, anger or shock. It typically ends with an exclamation mark (!).


The following are examples of exclamatory sentences expressing the various emotions.
Wait! I’m coming along. (Excitement)
We thought you weren’t coming! (Surprise)
But you said you would pay me back today! (Anger)
We read how the children were treated. Shocking! (Shocked)
I won the bet! (Happiness) 
I’m really going to miss you. (Sadness)