English Grammar for the Utterly Confused - Laurie Rozakis 2003
The Four Different Sentence Functions
Chapter 8 Writing Correct and Complete Sentences
Part 3 Sentence Sense
In addition to classifying sentences by the number of clauses they contain, we can pigeonhole sentences according to their function. There are four sentence functions in English: declarative, exclamatory, interrogative, and imperative.
1. Declarative sentences state an idea. They end with a period.
Grasshoppers contain more than 60 percent protein.
Insects are rich in necessary vitamins and minerals.
Crickets are packed with calcium, a mineral crucial for bone growth.
Termites and caterpillars are a rich source of iron.
2. Exclamatory sentences show strong emotions. They end with an exclamation mark.
I can’t believe you left the car at the station overnight!
What a mess you made in the kitchen!
Our evening is ruined!
The china is smashed!
3. Interrogative sentences ask a question. They end with a question mark.
Who would eat bugs?
Where did you put the eraser?
Would you please help me with this package?
What do you call this dish?
4. Imperative sentences give orders or directions, and so end with a period or an exclamation mark. Imperative sentences often omit the subject, as in a command.
Take this route to save 5 miles.
Clean up your room!
Sit down and listen!
Fasten your seatbelts when the sign is illuminated.