Coordinating Conjunctions

There are three main coordinating conjunctions in English:

• AND: This coordinating conjunction introduces an additional item: The tortoise and the hare are going to have a race.
• BUT: This coordinating conjunction introduces a contrasting item: The hare is fast but foolish.
• OR: This coordinating conjunction introduces an alternative item: Who do you think will win: the tortoise or the hare?

There are some other coordinating conjunctions, but they are used much less frequently:

• NOR: This coordinating conjunction introduces a negated item: The tortoise is not boastful, nor is he lazy.
• YET: This coordinating conjunction introduces a contrasting item: The hare is fast, yet he loses the race.
  
• FOR: This coordinating conjunction introduces an explanatory item: The tortoise wins the race, for he is slow and steady.
• SO: This coordinating conjunction introduces a resulting item: The tortoise reached the finish line first, so he won the race.

PUNCTUATION. When a coordinating conjunction is used to join two independent clauses, you usually want to have a comma before the conjunction:

• The hare challenges the tortoise to a race, AND the tortoise agrees.
• The hare starts out ahead, BUT he stops to take a nap.
• The hare better wake up, OR he is going to lose the race.

You do NOT need to have a comma when the conjunction is joining single words or phrases:

• The tortoise AND the hare are going to have a race.
• The hare is fast BUT foolish.
• Who do you think will win: the tortoise OR the hare?

SERIES. When you are joining more than two items, you use the conjunction to join the final two items; the other items are joined by commas.

• The hare starts out fast, slows down, AND stops to take a nap.
• The tortoise starts out slow, never stops, AND wins the race.

BEGINNING A SENTENCE WITH AND. If you are tempted to use "and" at the beginning of a sentence, there is almost always a better alternative. Example:
The tortoise won the race. And all the animals were so proud of him!

• Try combining the sentence with the previous sentence by using a comma:
  The tortoise won the race, and all the animals were so proud of him!
• Try just leaving out the "and" completely:
  The tortoise won the race. All the animals were so proud of him!
• Try using a different word or phrase as the connector:
  The tortoise won the race. Plus, all the animals were so proud of him!

BEGINNING A SENTENCE WITH BUT. If you are tempted to use "but" at the beginning of a sentence, there is almost always a better alternative. Example:
The hare lose the race. But he learned a good lesson.

• Combine the two sentences, and remember to use a comma before the "but" clause:
  The hare lost the race, but he learned a good lesson.
• Use a conjunctive adverb to connect the ideas, either in a single sentence or in separate sentences:
  The hare lost the race; however, he learned a good lesson.
  The hare lost the race. However, he learned a good lesson.

"HOWEVER" IS NOT A COORDINATING CONJUNCTION. You cannot use the word "however" with a comma to coordinate two independent clauses.
The hare lost the race, however he learned a good lesson.
That is a type of run-on sentence called a "comma splice." To avoid this error, you need to use the word "but" as the coordinating conjunction, or you can use a semicolon instead of a comma.

• The hare lost the race, but he learned a good lesson.
• The hare lost the race; however, he learned a good lesson.

(For more about this use of "however," see this page about Conjunctive Adverbs.)

Find out more here: CONJUNCTIONS.

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The hare starts out fast,
but then he slows down to take a nap.

(image source)

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