Conjunctions in essays and dissertations

Conjunctions in Academic Writing 

There are many stages to writing an essay, dissertation or thesis. The penultimate stage is writing detailed notes and a draft version of the paper which form the basis of the completed work. If an essay or other written work is to be successful and to impress the examiner, it is essential that the text flows naturally and that every argument is presented clearly. If sentences are too short, the thesis will appear as a list of statements which the reader will find most uninteresting. However, If sentences are too long, it is likely that the text will be unclear and fail to present the argument effectively. These two potential hazards can be avoided by the correct use of conjunctions.

What are conjunctions?

Conjunctions are words that connect phrases, clauses and sentences, enabling the text to flow well and clearly. The most frequently used conjunctions are: ‘and’, ‘but’ and ‘because’.

Is it incorrect to begin a sentence with a conjunction?

Many people still remember being told in school, ‘Never start a sentence with a conjunction’. The argument for this is that a conjunction is a ‘joining’ word. However, there Is no specific grammar rule that a sentence cannot begin with a conjunction. For instance, It is argued that Shakespeare often began sentences with a conjunction. In fictional work and in spoken language, this can be effective; for example: There was a full moon. And it was cold. This is mainly a matter of the author’s style. Generally, in academic style, it is better not to begin a sentence with a conjunction. 

The conjunction ‘and’

A simple example of this conjunction improving the flow of the text is:

The essay was informative. It was interesting to read.

The essay was informative and interesting to read. 

Using ‘and’ with commas

Although some people argue that a comma should never be used with ‘and’, it is sometimes necessary to do so; for example: There is abundant life on the earth and the moon has no signs of life. There should be a comma after ‘earth’, otherwise it gives the impression that both the earth and the moon have abundant life. A better way of saying this would be to use ‘but’ rather than ‘and’. There is abundant life on the earth, but the moon has no signs of life. 

Overusing ‘and’

The conjunction ‘and’ should not be overused in academic writing as it gives the impression of an amateur or immature writing style; for example:

The university offers courses in physics and mathematics and astronomy and chemistry.

It would be better to say:

The university offers courses in physics, mathematics, astronomy and chemistry.

A further argument arises as to whether there should be a comma after ‘astronomy’. This is known as the serial or Oxford comma which can be a controversial topic. If you are unsure about this, it is essential that you consult the style guide of your university. There are some occasions where the Oxford comma is necessary in order to avoid confusion, for example: When I returned home, I was greeted by my parents, the dog and the cat. The addition of the Oxford comma clarifies that the writer’s parents are not a dog and a cat! When I returned home, I was greeted by my parents, the dog, and the cat. However, others argue that common sense dictates the meaning. 

Using ‘and’ in progression and comparison

Consider this sentence: The average age of the ships in the fleet is becoming older and older. This refers to a gradual aging of the fleet. However, in academic writing it may be better to say: The average age of the ships in the fleet is becoming increasingly older.

The word ‘and’ can also be used in comparison, for example; There are cars and cars. This means that some cars are better than others. 

The conjunction ‘or’

When using ‘or’, it should be remembered that it presents one of two (or more) alternatives, for example: The walls should be painted blue or green. This conjunction can be used as a pair ‘either…or’ or as a negative ‘neither…nor’, for example: I have neither the time nor the inclination to read this book.

The conjunction ‘because’

This is a matter of cause and effect, for example:

The written examination was cancelled because of the pandemic.

Another use of ‘because’ can have a different meaning:

I believe that the shop is closing because the manager told me.

This does not mean that the reason for the closure is because the manager told the writer, but rather the writer believes this to be true because the manager told him. It would be better to express this differently: The manager told me that the shop is closing; therefore, I believe this to be true.

The conjunction ‘but’

This conjunction can link two clauses where one justifies the other, for example:

The experiment was time-consuming but it verified the hypothesis. 

The word ‘but’ can also be used as a preposition to mean ‘except’:

Everyone but the principal knew that the students were planning a sit-in.

In spoken language ‘but’ is increasingly used as a standalone expression:

Heavy rain fell all night …  But. … There were no floods.

This style should be avoided in academic writing.

Subject-Verb Agreement

Agreement between subject and verb is essential in academic writing, and extra care needs to be taken when ‘and’ is used, in which case the verb is almost always plural:

Philosophy, history and religion are the main subjects taught at the university. 

However, please note the following cases where the singular is used: 

The dissertation, which presents the results of the study on meteorology, climate change and biodiversity isinteresting to read. (Singular verb because ‘dissertation’ is the subject). 

Another example of this is: Harrow and Wealdstone is a railway station near London.

The singular is used here because the name refers to one railway station. However, it would be correct to say: Harrow and Wealdstone are two communities served by one railway station. 


Allen, Robert, 1999. Pocket Fowler’s Modern English Usage. 2nd ed, 2008: Oxford; Oxford University Press. 

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