You might have seen these terms floating around. Clauses are the building blocks of sentences. They’re groups of related words (phrases) that contain both a subject and a verb. When a clause can stand alone as a complete sentence with a clear meaning, it’s considered independent. If it only makes sense when you join it with another clause, it’s dependent (or subordinate). For example, “in the morning” is a phrase. You can make it a clause by adding the subject and verb combination “she ran,” as in “She ran in the morning.”
Coordination and Subordination
So you know that independent clauses can be standalone sentences. Great. But not every sentence will be made of just one clause. If two clauses are closely related, you can connect them into one sentence. Just remember that you need at least one clause to be independent for the sentence to make sense. Coordination is when you connect two or more independent clauses. Subordination involves connecting an independent clause and a subordinate clause.
Conjunctions are connective words that help you join clauses. You can remember the seven coordinating conjunctions with the mnemonic device FANBOYS: for, and, nor, but, or, yet, and so. These are the ones you’ll use to coordinate independent clauses.
A subordinating conjunction is a word or short phrase that begins a subordinate clause. It helps to establish its relationship between the independent and dependent clause. A few examples are although, if, because, while, and rather than. A subordinate clause can appear at the beginning, middle, or end of a sentence.
If you’re connecting two independent clauses with a coordinating conjunction, there should be a comma before it. Arthur Miller demonstrates this in a line from Death of a Salesman: “I don’t know the reason for it, but they just pass me by.” Each clause is a complete thought on its own. They work better as a unit because the second clause expands upon the meaning of the first. The conjunction and comma help to show that the clauses are still separate thoughts. If they’d been forced together without the comma or conjunction, this would be a run-on sentence.
If Miller had just used used a comma (without a conjunction) to separate the clauses, the result would be what’s known as a comma splice. It’s best to avoid comma splices. If you want to join two independent clauses without a conjunction, you can use a semicolon (which is actually designed for that): “I don’t know the reason for it; they just pass me by.”
An independent clause can also have a subordinate role if it begins with a subordinating conjunction. There’s an example of this in The Light Fantastic by Terry Pratchett: “A boat smaller than a thimble caught Galder’s eye for a moment before the rush carried it through the walls and away.” This time, the subordinate clause finishes the sentence, and it doesn’t need a comma.