by Davy Kraken
A library featuring commonly committed errors of the English language.
|A sentence can consist of nothing more than a subject and a verb. For example, the shortest verse in the Bible is the famous John 11:35: “Jesus wept.” Sentence fragments are often employed for effect in both oral and written communication, but no truly proper sentence can exist without those two ingredients.
A clause consists of a subject, verb, and any related words. An independent clause, like Jesus wept, can exist as a sentence on its own, while a dependent clause cannot. In the previous sentence, the part preceding the comma was an independent clause, and the part following it was a dependent clause. Can you see why? If I just wrote While a dependent clause cannot and called it a complete sentence, you’d be asking, “Huh? Aren’t you missing something?” Dependent clauses begin with what are called subordinating conjunctions: words like as, if, because, or since.
A complete sentence must have at least one independent clause, but sentences often consist of more independent clauses or dependent clauses and many possible types of phrases. The order and type of clauses in a sentence determine what punctuation, if any, should be used to separate them.
The clauses should be joined with a comma followed by an appropriate one of the seven coordinating conjunctions: and, but, for, nor, or, so, and yet. Alternatively, independent clauses can be linked via just a semicolon. If nothing but a comma stands between them, a comma splice results. See "Comma Splices and Fused Sentences" for more information on this grammatical error.
When a dependent clause precedes an independent clause, there should always be a comma between them.
This is the fuzziest scenario. In this case, a comma usually doesn’t appear between the clauses. One exception is when the subordinating conjunction expresses a contrast, which is often found in such words as although, even though, whereas, or while. The other example is when the dependent clause is a non-essential relative clause. See "Relative Clauses" for more information on relative clauses.
I didn’t want to get out of bed, so I hit the snooze button.
No one has lived in that house since Mrs. Ballenger died.
Because you misbehaved, you have to spend the night in your room.
I would never tell her the dress makes her look fat.
The subordinating conjunction that can often be omitted.
Though the strawberry milkshakes are my favorite, I also like chocolate, and I’ll even have a vanilla one if the mood strikes me.
I wanted to go to the game, but because I had other obligations, I couldn’t.
Notice the comma between the first independent clause and the dependent clause. This is because but acts as a coordinating conjunction for everything following it.