By Chris Cherry
Oftentimes, a sentence is defined as having a subject and a verb and expressing an idea. (In fact, I talk about sentences much this way in another handout.) But many sentences have multiple nouns and verbs. For example: The problem that Rebecca had with Andre was that he sometimes started fights when he was bored. That sentence has several subjects and verbs in it. What gives?
In truth, the usual definition of a sentence doesn’t define a sentence at all, but a clause. A clause is a group of words that contains a subject and verb and expresses an idea. A clause can stand on its own (an independent clause) or rely on another clause for context (a dependent clause). A simple sentence is one that contains a single independent clause.
A compound sentence is made up of two independent clauses linked together with a semicolon, comma and semicolon, or comma and the words and, but, so, or, nor, for, or yet.
A complex sentence is made up of an independent clause and at least one dependent clause. Notice in the previous sentence that both of those clauses could be sentences themselves. Dependent clauses don’t work that way. There are several types of dependent clauses.
In this sentence, the clause “that bananas are berries” is the object of the sentence. It acts like a noun. It’s the thing that I read.
An adjective clause works like an adjective. Like an adjective, it describes a noun. Adjective clauses follow the nouns they describe and usually begin with the words that, which, who, whose, or whom. (Another name for this type of clause is “relative clause”, so these words are called “relative pronouns.”)
The clause “who teaches piano” describes the guy like an adjective does. Note that, in this case, the word who is the subject of the clause, because it’s being used as a pronoun.
An adverb clause is a clause that (surprise!) works like an adverb. It describes the verb in a sentence. There are many words that can begin an adverb clause, depending on how you want to describe the action of a sentence.
You can explain when an action is happening by using after, as, before, once, since, until, when, whenever, and while. You can explain where an action is happening by using where or wherever. You can explain why the action is happening by using because, since, in order that, or so that. And there are even more options; although, if, that, though, unless, while, even if, even though, provided that, and rather than can all begin an adverb clause.
The adverb clause in this case describes the reason why we left.
Adverb clauses usually come after the verb (and the object if the sentence has one). However, they can also come at the beginning of the sentence. This is a great way to vary up your sentence structure.
In this case, the adverb clause still describes the action, even though it comes at the beginning of the sentence. Remember: any time you begin a sentence with an adverb clause, follow the clause with a comma.