1. Sentences

2. End Marks and Sentence Purpose
Simple Sentences

3. End Marks: Rules
An end mark is a mark of punctuation place at the end of the sentence. English uses three kinds of end marks:
the period
the question mark
the exclamation point

4. End Marks: Rules Use a period at the end of a sentence.
The manatee is also called a sea cow.
It is a mammal that lives in the ocean.
Use a question mark at the end of a question.
Have you ever seen a manatee?
Did it look like a cow to you?
Use an exclamation point at the end of an exclamation. This type of statement should show emotion.
That’s amazing!
Look! There’s a manatee over there.
Use a period or an exclamation point at the end of a request or command.
Please read this. (a request)
Give me that! (a command)

5. End Marks: Rules Use a period after most abbreviations:
Personal names: Joel H. Fairweather, M.E. Gadski
Titles used with names: Mr., Mrs., Ms., Jr., Sr., Dr.
States (except the two-letter abbreviations)
Ark., Calif., Minn. but not MN, WI, IA
Addresses: St., Ave., P.O. Box
Organizations and Companies: Co., Inc., Corp., Assn.
Times: A.M., P.M., B.C., A.D.
NOTE: Most units of measure are abbreviated without periods. The exception is inch—in.

6. Classifying Sentences by Purpose
Sentences can be classified in many ways; sentence type and sentence purpose are just two of them.
A declarative sentence is a statement. Use a period.
An interrogative sentence is a question. Use a question mark.
An imperative sentence gives a command or a request. Use a exclamation point or a period.
An exclamatory sentence shows emotion or strong feeling. Use an exclamation point.
A conditional sentence expresses a wish using an If. . .then statement. Use a period.