Many universities award as much as 5% of your essay’s marks for good spelling and grammar.  Not only can you lose marks through errors but they also give your paper the look and feel of a lower grade.

If you’re proofreading an essay for the first time, here are some common mistakes that students make to watch out for:


This one may seem fairly obvious but don’t rely on your computer’s spell checker to correct your spelling.  Not only will it miss things but English language depends on context and this is extremely hard to teach a computer.  So check your essay carefully yourself and if you’re unsure, ask a friend to go through it for you.

To ensure you don’t miss anything, use a sheet of paper to go through the essay line by line.  It’s a little easier to do this if you print a copy.

Another trick is to read the paper slowly out loud.  This helps you pick up on double words or missed words. Make sure you’re actually reading what is on the page and not what you think is on the page!


Fragmented sentences are easy to find because they don’t make sense when they are said on their own.

For example:

I went to a party.  Because it sounded like fun.

“Because it sounded like fun” is a fragment.  If you said it on its own with nothing else, it would make no sense.  What sounded like fun? Technically, the way to avoid fragments is to ensure that each sentence has a subject.  In this case, the party is the subject that is missing from the sentence.  “I went to a party, because it sounded like fun” becomes a sentence because now it has a subject.

Comma splices

Here are some examples:

I enjoy sport, I especially enjoy Tennis, Tennis is a fantastic sport to watch.

My father bought a new car, he put me on the insurance so that I could drive it, I was very happy.

Each of the above example sentences ought to be 3 sentences or have some other form of punctuation to separate them.  A hyphen or semi colon sometimes works.


I enjoy sport. I especially enjoy Tennis – Tennis is a fantastic sport to watch.

My father bought a new car.  He put me on the insurance so that I could drive it – I was very happy.

Run on sentences

It is genuinely astounding how many professional writers use run-on sentences.

Technically, a run-on sentence is one that has more than one independent clause. All you need to look out for are sentences that really ought to be two or more sentences, or require some extra words.

For example:

I went walking with my dog it poured it down.

In an example like this, be careful not to simply insert a comma as this would be a comma splice!

Subject/verb agreement

The subject and verb in each of your sentences should match in number.  If the subject is plural, the verb should be as well.

For example:

Teachers at college classrooms is usually extremely busy.

Since ‘teachers’ is a plural, the verb should be ‘are’.


Look carefully through your paper for words that end with an ‘s’ and check that you have used the correct apostrophe.  If the ‘s’ is used to indicate possession – such as Simon’s car, or Lee’s television -there should be an apostrophe.

A common mistake that students make is to use an apostrophe with an acronym.  For example, GCSE’s, or CFM’s.  This is not needed and would be indicating possession which would not make sense!

Apostrophes are not used to make a word plural (e.g. “there are many car’s” is incorrect).

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