Punctuation in Types of Sentences

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Learning rules for how and when to punctuate a sentence can be difficult, especially when you consider that different types of sentences call for different types of punctuation. This handout should help to clarify not only the types of sentences, but also what punctuation to use in what situation.

Punctuation in Types of Sentences

Independent clause: a clause that has a subject and a verb and can stand alone; a complete sentence

Dependent clause: a clause that has a subject and a verb but cannot stand alone; an incomplete sentence

Simple: composed of 1 independent clause.

No standard punctuation.

Compound: composed of 2 or more independent clauses.

Join 2 independent clauses by a comma and a coordinating conjunction (and, but, or, for, nor, so).

Road construction can be inconvenient, but it is necessary.

Join 2 independent clauses by a colon when you wish to emphasize the second clause.

Road construction in Dallas has hindered travel around town: parts of Main, Fifth, and West Street are closed during the construction.

Join 2 independent clauses by a semicolon when the second clause restates the first or when the two clauses are of equal emphasis.

Road construction in Dallas has hindered travel around town; streets have become covered with bulldozers, trucks, and cones.

Complex: composed of 1 or more dependent clauses and 1 or more independent clauses.

Join an introductory dependent clause with the independent clause by a comma.

Because road construction has hindered travel around town, many people have opted to ride bicycles or walk to work.

Many people have opted to ride bicycles or walk to work because road construction has hindered travel around town.

Compound-Complex: composed of 1 or more dependent clauses and 2 or more independent clauses.

Join an introductory dependent clause with an independent clause with a comma. Separate 2 independent clauses with a comma and a coordinating conjunction (and, but, or, for, nor, so).

When it is filtered, water is cleaner, and it tastes better.

Join an introductory dependent clause with an independent clause with a comma. Separate 2 independent clauses by a colon when you wish to emphasize the second clause.

Whenever it is possible, you should filter your water: filtered water is cleaner and tastes better.

Join an introductory dependent clause with an independent clause with a comma. Separate 2 independent clauses by a semicolon when the second clause restates the first or when the two clauses are of equal emphasis.

When it is filtered, water is cleaner and tastes better; all things considered, it is better for you.