7 Most Common Grammar and Punctuation Errors: Explanations, Tips, and Examples

Paul “Bear” Bryant, a legendary American college football player and coach, once said, “When you make a mistake, there are only three things you should ever do about it: admit it, learn from it, and don’t repeat it.” These are the words of a wise man and an experienced coach who has helped hundreds of players reach their full potential. However, living up to this high standard might be much harder than it seems.

We often unwillingly repeat some grammar mistakes so many times that we eventually get used to them. We feel annoyed by these impostors when we spot them in our essays, homework assignments, and emails, and yet we keep making them over and over again.

Do not let errors spoil the fun of writing a clear and engaging text! There are many solutions to this problem: for example, you can use a grammar checker, turn to a professional paper writing service online, or hire an editor.

There is one more simple and effective solution – read the article below, find out what the most common grammar and punctuation mistakes are, and train your mind to stay on the lookout for them.


1. I and me

It seems these two personal pronouns are impossible to confuse. However, the difference between them slowly fades as you discover more and more tricky contexts in which they can be used. For example, which of the two sentences is correct?

  1. a) Jane sent a beautiful wedding invitation to Alex and I.
  2. b) Jane sent a beautiful wedding invitation to Alex and me.

We bet you have guessed correctly – the second variant is right: Jane sent a beautiful wedding invitation to Alex and me. Here is another riddle for you – choose the correct variant:

  1. a) Alex and I bought a huge bouquet of white roses for Jane.
  2. b) Alex and me bought a huge bouquet of white roses for Jane.

Exactly! The first variant is correct. The rule is quite simple: “I” is a subject and is used before the relevant verb. “Me” is an object and is used after the relevant verb. So, the whole story runs like this:

Jane sent a beautiful wedding invitation to Alex and me. Alex and I bought a huge bouquet of white roses for Jane. It is such a pity we never gave Jane the roses because she ran away with her fiancé’s best man.

2. they’re/their/there

“They’re” is a contracted form of “they are.” “Their” is a possessive pronoun that indicates that something belongs to or is associated with a group of people or things. “There” is an adverb focusing attention on some particular place. It is often a part of “there is”/”there are” phrases used to say that something exists somewhere.

e.g., Look at the kids! They’re so hungry that their stomachs are rumbling! There are some really good food stalls across the street – let’s go there!

Are you hungry for some more common grammar mistakes?

3. affect/effect

These two words are incredibly easy to confuse as they are homophones and only one letter away from each other. In addition, both refer to producing an impact on something or somebody. “Affect” is usually a verb, and it means “to influence or to change.” “Effect” is most commonly a noun denoting the result of such a change or influence.

e.g., This herbal tea may briefly affect your ability to concentrate and perform complex tasks, but it also has a highly beneficial effect on your nervous system. And anyway, you are already late with that assignment, so why worry?

There is a simple mnemonic trick that can be used to avoid mistakes: “Affect” is an Action, “Effect” is an End result.

4. lie/lay

These two verbs often get confused as they look and sound similar. If you put an object down on some surface, you LAY it. The verb “lay” is transitive and requires an object, i.e., you always need to specify what precisely it is that you are putting down. If you assume a horizontal position planning to rest a little, you LIE down. The intransitive verb “lie” does not require an object.

e.g., When you are on a picnic, you can lay a blanket on the grass, lie down, and relax a little.

A picnic is always a good idea, even when the parks are closed due to the pandemic and you only have a tiny balcony at your disposal.

5. then/than

We have all made this mistake, so there is no need to worry – you are not alone! Just remember that “then” is an adverb referring to a time sequence while “than” is a conjunction that allows you to compare people and things.

e.g., I thought we would work on our project and then watch a movie. But the homework turned out to be much more difficult than we expected, so we decided to start with a movie.

6. Title Capitalization

There is a simple trick: capitalize every single word in your title and then lowercase articles, coordinating conjunctions, prepositions, and ‘to’ in an infinitive with the exception of the first and the last word.

e.g., An Ultimate Beginner’s Guide to the Most Essential Capitalization Rules: How to Decide What to Capitalize in a Title.

7. Commas before Dependent Clauses

There is internal logic in this rule: if a clause is independent, it means that it is a serious and adult clause, so it can afford a comma; but if the clause is a dependent one, it cannot be separated from its loving parent – the main clause – by a comma.

e.g., I wanted to buy an ice cream cone but then decided against it.

I wanted to buy an ice cream cone, but then I thought I would rather buy two.


Final Thoughts

One last piece of advice from us: be kind to yourself! Develop a growth mindset that will allow you to see every situation as an opportunity to learn. If you have not mastered a particularly tricky grammar rule, do not despair, you are just not there YET. And do not get discouraged by mistakes – they are there to help you become your better self!


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