End Punctuation Help

Periods

The most common form of end punctuation, the period (.) indicates the end of declarative sentences (statements of facts) and imperative sentences (simple commands or requests).

Examples:

Periods are also used with common abbreviations, such as months, days, and measurements (Dec., Mon., .02). Note that periods are not used for acronyms—abbreviations that use all capital letters (NATO, CEO, DNA) or for postal state abbreviations (SD, AL, NJ). Finally, periods are used after a person's initials (T.S. Eliot, W.C. Fields) and for titles such as Dr., Mr., or Gov. If a sentence ends with an abbreviation that has an end period, use it as the end mark, unless the sentence needs an exclamation point or question mark.

Examples:

Tip: Always identify an acronym before you use it unless you are sure the average reader would know it because it is used more often than the words it stands for, such as AIDS or NATO. For example, you might write about the Federal Bureau of Investigation (FBI).

Question Marks

The question mark (?) indicates the end of an interrogatory sentence (direct question).

Examples:

Indirect questions are statements that only sound like questions, so they end with a period.

Examples:

Exclamation Points

An exclamation point (!) at the end of a sentence indicates strong feeling or authoritative commands. Interjections—free-standing words or phrases that express strong feelings—are also punctuated with exclamation points.

Examples:

Tip: Using two or more exclamation points at the end of a sentence for extra emphasis may seem like a good idea, but in fact it is incorrect and it may be thought of as rude.

Exercises for this concept can be found at End Punctuation Practice