Text: Conjunctions

Conjunctions are the words that join sentences, phrases, and other words together. Conjunctions are divided into several categories, all of which follow different rules. We will discuss coordinating conjunctions, adverbial conjunctions, and correlative conjunctions.

Coordinating Conjunctions

Compass iconThe most common conjunctions are andor, and but. These are all coordinating conjunctions. Coordinating conjunctions are conjunctions that join, or coordinate, two or more equivalent items (such as words, phrases, or sentences). The mnemonic acronym FANBOYS can be used to remember the most common coordinating conjunctions: for, and, nor, but, oryet, and so.

  • For: presents a reason (“They do not gamble or smoke, for they are ascetics.”)
  • And: presents non-contrasting items or ideas (“They gamble, and they smoke.”)
  • Nor: presents a non-contrasting negative idea (“They do not gamble, nor do they smoke.”)
  • But: presents a contrast or exception (“They gamble, but they don’t smoke.”)
  • Or: presents an alternative item or idea (“Every day they gamble, or they smoke.”)
  • Yet: presents a contrast or exception (“They gamble, yet they don’t smoke.”)
  • So: presents a consequence (“He gambled well last night, so he smoked a cigar to celebrate.”)

Here are some examples of these used in sentences:

  • Nuclear-powered artificial hearts proved to be complicated, bulky, and expensive.
  • In the 1960s, artificial heart devices did not fit well and tended to obstruct the flow of venous blood into the right atrium.
  • The blood vessels leading to the device tended to kink, obstructing the filling of the chambers and resulting in inadequate output.
  • Any external injury or internal injury put patients at risk of uncontrolled bleeding because the small clots that formed throughout the circulatory system used up so much of the clotting factor.
  • The current from the storage batteries can power lights, but the current for appliances must be modified within an inverter.

As you can see from the examples above, a comma only appears before these conjunctions sometimes. So how can you tell if you need a comma or not? There are three general rules to help you decide.

Rule 1: Joining Two Complete Ideas

Let’s look back at one of our example sentences:

The current from the storage batteries can power lights, but the current for appliances must be modified within an inverter.

There are two complete ideas in this sentence. A complete idea has both a subject (a noun or pronoun) and a verb. The subjects have been italicized, and the verbs bolded:

  • the current from the storage batteries can power lights
  • the current for appliances must be modified within an inverter.

Because each of these ideas could stand alone as a sentence, the coordinating conjunction that joins them must be preceded by a comma. Otherwise you’ll have a run-on sentence.

Run-on sentences are one of the most common errors in college-level writing. Mastering the partnership between commas and coordinating conjunctions will go a long way towards resolving many run-on sentence issues in your writing.

Rule 2: Joining Two Similar Items

So what if there’s only one complete idea, but two subjects or two verbs?

  • Any external injury or internal injury put patients at risk of uncontrolled bleeding because the small clots that formed throughout the circulatory system used up so much of the clotting factor.
  • In the 1960s, artificial heart devices did not fit well and tended to obstruct the flow of venous blood into the right atrium.

The first sentence has two subjects: external injury and internal injury. The second sentence has two verbs: did not fit well and tended to obstruct. In each sentence, the two similar items are separated from each other by a conjunction, but no comma is required.

Rule 3: Joining Three or More Similar Items

So what do you do if there are three or more items?

  • Anna loves to run, David loves to hike, and Luz loves to dance.
  • Fishing, hunting, and gathering were once the only ways for people do get food.
  • Emanuel has a very careful schedule planned for tomorrow. He needs to work, study, exercise, eat, and clean.

As you can see in the examples above, there is a comma after each item, including the item just prior to the conjunction. There is a little bit of contention about this, but overall, most styles prefer to keep the additional comma (also called the serial comma). We discuss the serial comma in more depth in Text: Commas.

Starting a Sentence

Many students are taught—and some style guides maintain—that English sentences should not start with coordinating conjunctions.

This video shows that this idea is not actually a rule. And it provides some background for why so many people may have adopted this writing convention:

Practice

Are the following sentences correctly punctuated?

  1. I heard some news on the radio about a fire and my family saw it on the television.
  2. The fire chief called in all his men, but ordered them to stay back.
  3. The building became engulfed in flames, so they stood by.
  4. They needed to examine everything for they did not think it was an accident.
  5. The police could not find the source of the fire, nor could the fire chief.

Adverbial Conjunctions

Icon of two thought bubblesAdverbial conjunctions link two separate thoughts or sentences. When used to separate thoughts, as in the example below, a comma is required on either side of the conjunction.

The first artificial hearts were made of smooth silicone rubber, which apparently caused excessive clotting and, therefore, uncontrolled bleeding.

When used to separate sentences, as in the examples below, a semicolon is required before the conjunction and a comma after.

  • The Kedeco produces 1200 watts in 17 mph winds using a 16-foot rotor; on the other hand, the Dunlite produces 2000 watts in 25 mph winds.
  • For short periods, the fibers were beneficial; however, the eventual buildup of fibrin on the inner surface of the device would impair its function.
  • The atria of the heart contribute a negligible amount of energy; in fact, the total power output of the heart is only about 2.5 watts.

Adverbial conjunctions include the following words; however, it is important to note that this is by no means a complete list.

therefore however in other words
thus then otherwise
nevertheless on the other hand in fact

Practice

Fill in the missing punctuation marks for the sentences below:

  1. Alícia works behind the counter in the family bakery after school __ however __ Benjamin doesn’t.
  2. On the one hand __ Benjamin loves goes to soccer games __ on the other hand __ he doesn’t like to play soccer.

Correlative Conjunctions

Balanced scales iconCorrelative conjunctions are word pairs that work together to join words and groups of words of equal weight in a sentence. This video will define this types of conjunction before it goes through five of the most common correlative conjunctions:

The table below shows some examples of correlative conjunctions being used in a sentence:

Correlative Conjunction Example
either…or You either do your work or prepare for a trip to the office. (Either do, or prepare)
neither…nor Neither the basketball team nor the football team is doing well.
not only…but (also) He is not only handsome, but also brilliant. (Not only A, but also B)
Not only is he handsome, but also he is brilliant. (Not only is he A, but also he is B.)
both…and Both the cross country team and the swimming team are doing well.
whether…or You must decide whether you stay or you go. (It’s up to you)
Whether you stay or you go, the film must start at 8 pm. (It’s not up to you)
just as…so Just as many Americans love basketball, so many Canadians love ice hockey.
as much…as Football is as much an addiction as it is a sport.
no sooner…than No sooner did she learn to ski, than the snow began to thaw.
rather…than I would rather swim than surf.
the…the The more you practice dribbling, the better you will be at it.
as…as Football is as fast as hockey (is (fast)).

Practice

Select the correct conjunction for each sentence:

  1. (Both / Not only) you but also Paul forgot to do the annual report last week.
  2. You will need to finish it by (either / neither) today or tomorrow. Just get it done by Friday.
  3. (Both / Not only) you and Paul have been wasting too much time.
  4. Not only (she yells / does she yell / is she yell) at me, but also she screams at me.
  5. Either (she stops / does she stop) yelling at me or I quit.
  6. She both (annoys / does she annoy) and angers me.

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