Punctuation Mark

Example

Rule

Period .

Every sentence ends with a period.

Today is Wednesday.

Put a period at the end of a sentence.

Comma ,

The man bought a shirt, pants, socks, and shoes.

* The man bought a shirt, pants, socks and shoes.

Use commas to separate items in a list.

The final comma before the "and" may be omitted if the items are short.

a) The couch is big, black, and comfortable.

b) The red, white, and blue shirt belongs to Tom.

c) That tall well-dressed older man is Tom.

Use commas to separate adjectives.

a) Always use commas for a series of adjectives after the verb.

b) Usually use commas for a series of adjectives giving the same kind of information before a noun.

c) Do not use commas for a series of adjectives giving different kinds of information.

a) The red-haired woman, sitting on the couch, is my mother.

b) The woman sitting on the couch is my mother.

Use commas to separate non-identifying adjective clauses and phrases.

a) Use a comma to separate an adjective clause / phrase from the independent clause if the adjective phrase is not needed to identify the subject.

b) Do not use a comma to separate an adjective clause / phrase from the independent clause if the adjective phrase is needed to identify the subject.

Sunday was cold and rainy, but Monday was hot and sunny.

Use a comma to separate coordinate clauses.

Linking words for coordinate clauses are "and", "or", "but", "yet".

The comma may be omitted in very short clauses.

b) I feel happy when the sun shines.

Use commas to separate dependent and independent clauses.

a) When the dependent clause begins the sentence, use a comma.

b) When the independent clause begins the sentence, do not use a comma.

Tom saw, to his surprise, the dog and cat playing together.

Use commas to separate interruptions within a clause.

Interruptions are separate words or phrases that break up the normal word order of a clause.

Semi-colon ;

Yesterday Bob won a million dollars; today he quit his job.

Bob won a million dollars; therefore, he quit his job.

Use a semi-colon to separate independent clauses.

Use a semi-colon when two independent clauses are joined in one sentence, without a coordinate linking word.

Bob started the day by quitting his job; then buying a brand new truck; and, finally, arranging a flight to Singapore.

Use semi-colons to separate long, complex items in a list.

Colon :

Tom wants to buy three things today: a shirt, a pair of pants, and a pair of shoes.

Use a colon to introduce a list.

Use a colon at the beginning of a list within a sentence.

Bob wants to quit his job today: he just won a million dollars.

Use a colon to introduce an explanation.

Quotation marks " "

The words "flammable" and "inflammable" are often confused.

Use quotation marks to offset or emphasize words.