INDEPENDENT & DEPENDENT CLAUSES: COORDINATION & SUBORDINATION
An independent person is one who can solve problems on his own, take care of his own needs, stand on his own two feet, so to speak. An independent clause (a clause is a group of words that contains at least one subject and one verb) is one that can stand on its own two feet--independently. You can join independent clauses if you want to. This is called coordination.
A dependent person is one who needs help from another, more independent person. A dependent person needs to lean on someone stronger. A dependent clause is one that cannot stand on its own two feet--it needs an independent clause to lean on. You must join a dependent clause to an independent one. This is called subordination.
Independent clauses are strong
Compare an independent clause to the ideal roommate: She cleans up after herself, pays her share of the bills, never forgets to turn off the iron, and can fix a leaky faucet. Like the ideal roommate, an independent clause lacks nothing to stand on its own. For example, each of the following independent clauses can stand alone:
Jennifer put a new washer in the bathroom faucet before leaving for the party.
Mai figured out how to fix the garbage disposal.
The clauses above contain a subject and a verb, and they finish the thought they have started; they are complete simple sentences. For the sake of variety, however, you will often want to combine simple sentences using coordination to create compound sentences. You can choose one of two methods:
The most used coordinating conjunctions are often referred to as the FANBOYS (for, and, nor, but, or, yet, so). When you use one of the FANBOYS between independent clauses, you signal that the clauses are equal (sort of like how two independent roommates are equals). These two methods of coordination are demonstrated below:
Jennifer put a new washer in the bathroom faucet before leaving for the party; Mai figured out how to fix the garbage disposal.
Jennifer put a new washer in the bathroom faucet before leaving for the party, and Mai figured out how to fix the garbage disposal.
If you choose to coordinate two independent clauses using a semicolon, you have another option. You may choose to add a conjunctive adverb (followed by a comma-the adverb acts rather like an introductory phrase) after the semicolon:
Jennifer put a new washer in the bathroom faucet before leaving for the party; moreover, Mai figured out how to fix the garbage disposal.
A conjunctive adverb adds meaning or clarifies the relationship between the two clauses. See how choosing a different conjunctive adverb subtly changes the meaning of the pair:
Jennifer put a new washer in the bathroom faucet before leaving for the party; however, Mai figured out how to fix the garbage disposal.
The pattern, with appropriate punctuation (and yes, the punctuation counts) is as follows:
Coordinating Independent Clauses | |||
Method 1 Semicolon | Independent clause | ; | Independent clause |
Semicolon with conjunctive adverb and comma | Independent clause | ;moreover, ;however, ;consequently, ;indeed, ;nevertheless, ;therefore, | Independent clause |
Method 2 Comma and coordinating conjunction | Independent clause | , for , and , nor , but , or , yet , so | Independent clause |
(Note: Do not try to join two independent clauses with a simple comma. This error is called a comma splice. Furthermore, do not try to join two independent clauses with a coordinating conjunction alone, omitting the comma. This error is called a run-on. For more on these errors, see the TIP Sheet Comma Splices and Run-on Sentences.)
Dependent clauses are needy
In contrast to an independent clause, a dependent clause is incomplete; it is a type of sentence fragment. (For more information, see the TIP Sheet Fragments.) A dependent clause may contain a subject and a verb, but it begins a thought that it doesn't finish:
Because Amy left the iron on.
When the firemen arrived at the dorm.
The words that are to blame for making the above dependent clauses dependent are the words because and when. Inquiring minds want to know-what happened as a result of the iron being left on? What happened when the fire department reached the dorm? Like a needy roommate, these dependent clauses need to lean on something stronger. In the following examples we have added independent clauses for the dependent clauses to lean on:
The dorm's obsolete wiring melted and started a fire because Amy left the iron on.
Jennifer and Mai had already put out the fire when the firemen arrive at the dorm.
When you join a dependent clause to an independent clause, you are not joining equals. One side of the resulting sentence (the independent clause) is stronger, and the other side (the dependent clause) is weaker, or subordinate. (If you are a subordinate at work, you do as you're told.) The words used to join unequal pairs of clauses are called subordinating conjunctions.
But even here you have choices. Just because the independent clause is stronger, it doesn't have to always go first. (Sometimes the stronger person holds the door open to allow the person on crutches to enter first.) You could just as well write the following:
Because Amy left the iron on, the dorm's obsolete wiring melted and started a fire.
When the firemen arrived at the dorm, Jennifer and Mai had already put out the fire.
The important thing to remember about subordination is that the punctuationdiffers depending on whether the independent or the dependent clause "enters" first. If the dependent clause is first (again, rather like an introduction to the main clause), it is followed by a comma (like in this sentence and the next). If the independent clause comes first, no punctuation separates the two.
The pattern, with appropriate punctuation, is as follows:
Subordinating Dependent Clauses | |||
Method 1 Independent clause first | Independent clause | (No punctuation) | Dependent Clause |
Method 2 Dependent clause first | Dependent clause | , (comma) | Independent Clause |
For variety or to fine-tune meaning, you may choose to combine two independent clauses, making one of the clauses subordinate to the other with the addition of a subordinating conjunction:
While Jennifer put a new washer in the bathroom faucet, Mai figured out how to fix the garbage disposal.
Jennifer put a new washer in the bathroom faucet since Mai was figuring out how to fix the garbage disposal.
Here is a partial list of subordinating conjunctions. (Some textbooks call them "dependent-making words," or "dependent marker words.")
Common Subordinating Conjunctions | ||
after although as (as if) because before even though if | in order that rather than since so that than that though | unless until when whenever whereas whether while |
While other punctuation rules apply to particular kinds of clauses (for example, see the TIP Sheet Relative Pronouns: Restrictive and Nonrestrictive Clauses), if you learn to distinguish independent from dependent clauses and recognize subordinating conjunctions you will be more apt to avoid some common fragment and punctuation errors in your writing.