Sentence Types, with Notes on Punctuation

In this article, we will distinguish between four types of sentences.

1. A simple sentence contains only one independent clause. For example:

She rode her bike to class.

A simple sentence can include any number of phrases (such as "to class"). But as long as it contains no more than one independent clause, it will qualify as a simple sentence.

2. Complex sentences feature an independent clause and one or more subordinate clauses. For example:

They are the ones who ran the marathon.

You should punctuate such sentences according to the rules for restrictive and nonrestrictive clauses.

3. Compound sentences contain two or more independent clauses.

I went to the store, but it was closed.

The two independent clauses here are I went to the store and it was closed. You can punctuate a compound sentence in one of two ways:

Note that a comma on its own won't work, as in this example:

I went to the store, it was closed.

Neither will just a conjunction:

I went to the store to get some chips but it was closed for maintenance.

The first is a comma splice, and the second is a run-on. Avoid both of these.

4. Lastly, compound-complex sentences have two or more independent clauses and one or more subordinate clauses. For example:

I went to the store that sells tasty nachos, but it was closed.

Here, we can identify two independent clauses — I went to the store and It was closed — and one subordinate clause — that sells tasty nachos. To punctuate such sentences, focus on one clause at a time.

I went to the store

If the sentence ended here, a period would be appropriate. But instead of ending, the sentence continues with a restrictive clause— in this case, a clause beginning with that.

I went to the store that sells tasty nachos.

Remember our rule— a restrictive clause doesn't require a comma. Next step:

I went to the store that sells tasty nachos, but it was closed.

We need both a comma and a conjunction, to make sure we don't have a comma splice or run-on.

Try One on Your Own!

Look at the following sentence:

Twice last week they went to the theaters that are downtown. They saw Hamlet which is by William Shakespeare and then they saw Neil Simon's The Odd Couple.

Now, where would you put commas? Don't worry about fixing anything else in the passage.

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Analyzing Sentences

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