Conjunction Definition and Examples

The overpass is the conjunction
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A conjunction is the part of speech (or word class) that serves to connect words, phrases, clauses, or sentences. The common conjunctions—and, but, for, or, nor, so, and yet—join the elements of a coordinate structure and are thus called coordinating conjunctions. They connect words, phrases, and clauses of equal rank. In contrast, subordinating conjunctions connect clauses of unequal rank. Correlative conjunctions (such as neither...nor) pair things together as subjects or objects in a sentence, which is why they're also called pairing conjunctions.

Coordinating Conjunctions

You use coordinating conjunctions to connect two simple sentences with a comma. The two parts of the sentence, if split apart without the conjunction, could stand alone as sentences, as they both have a subject and a verb. Said another way, both parts of the sentence are independent clauses. They could also be joined with a semicolon.

  • With a coordinating conjunction: The white kitten was cute, but I chose the tabby instead.
  • With a coordinating conjunction: The white kitten was cute, yet I chose the tabby.
  • As two sentences: The white kitten was cute. I chose the tabby instead.
  • With a semicolon: The white kitten was cute; I chose the tabby instead. 

Coordinating conjunctions can also be used in items in a series or to create a compound subject or predicate.

  • Items in a series: Harry needed to pick a Siamese, tortoiseshell, calico, or a tabby cat.
  • Compound subject: Sheila and Harry both enjoyed playing with all the kittens.
  • Compound predicate: The kittens jumped​ around and played with all the people who came to greet them.

Notice that you don't use a comma before the conjunction in a compound predicate because both verbs belong to the same subject. There aren't two independent clauses.

A sentence style that employs many coordinate conjunctions is called polysyndeton, for example in the following: "Look at them all!" she said.

"There's a Labrador and a poodle and a German shepherd and a Chihuahua!"

Using Subordinating Clauses

A clause that couldn't stand alone as its own sentence is a dependent clause. When you connect a dependent clause to a sentence, you'll use a subordinating conjunction, such as in the following:

  • With a subordinating clause: It closed its eyes and purred at me when I picked up the tabby cat.
  • A second version of the sentence: When I picked up the tabby cat, it closed its eyes and purred at me.

You couldn't make the two clauses in this sentence into two sentences as they're written. "When I picked up the tabby cat," would be a sentence fragment (an incomplete thought) if read alone. Thus it's dependent (or subordinate) to the main clause of the sentence, the independent clause, which could stand alone: "It closed its eyes and purred at me."

Subordinating conjunctions can be classified into several groups:

  • Causality: because, since, as
  • Time: when, as soon as, before, after, while, by the time
  • Contrast/Opposition: though, although, even though, while, whereas, rather than
  • Condition: if, unless, even if, only if, in case, provided that, so that, whether

Subordinating Conjunctions List

The following is a list of subordinating conjunctions:

afteralthoughasas if
as long asas much asas soon asbecause
beforebut thatby the timeeven if
even thoughhowifin case
in order thatlestonly ifprovided that
rather thansinceso thatsupposing
thanthatthoughtill ('til)
unlessuntilwhenwhenever
wherewhereaswhereverwhether
whilewhy  

Paired Conjunctions

Correlative conjunctions pair things together and go in a set. They include either...or, neither...nor, not only...but also, both...and, not...nor, as...as. Whether you use a comma before the second conjunction depends on whether the clauses are independent or not (as in coordinating conjunctions above). 

  • Not two independent clauses: He picked out not only the Siamese cat but also the Labrador puppy.
  • Two independent clauses: Not only did the Siamese cat lick her, but the Labrador puppy also did.

Breaking the "Rules"

A past adage was to never start a sentence with a coordinating conjunction, but that's no longer.

Starting sentences with "but" or "and" can be used to break up long chunks of text or for rhythmic or dramatic effect. As with anything used for effect, though, don't overdo it; it won't stand out as desired if it's overused.

Practice Identifying Conjunctions

Examine the conjunctions in the following sentences. What type is each? 

  1. We needed to pick up milk, bread, and eggs from the store.
  2. You grab the pet food, and I will look for the other items.
  3. If you follow instructions, we could get this done faster.
  4. It's either my way or the highway.

Conjunction Exercises Answers

  1. and: coordinating conjunction connecting items in a series.
  2. and: coordinating conjunction connecting two independent clauses.
  3. if: subordinating conjunction
  4. either...or: correlative or paired conjunctions.