English grammar mistakes


Learning a language is a huge undertaking, not only in terms of vocabulary and speech, but also ultimately putting it all down in writing. English grammar has many pitfalls that are easy to fall into, and whether you’re a native speaker or a language learner, it is easy to make mistakes.

People that speak English as their first language are often tripped up by the finer intricacies of English grammar; with the same mistakes often cropping up time and time again. Here are some of the most common grammatical errors in English, and their correct usage.



There are a lot of rules to remember regarding apostrophes, take a few minutes to refresh your mind on how to use them, and save yourself some trouble in the future.

Apostrophes have two main uses:

  • To show that some letters have been taken out of a word to shorten it. The apostrophe goes where the letters have been removed.

E.g. Do not becomes don’t

  • To show belonging. To do this, you usually add: ‘s

E.g. The dog’s tail (shows that the tail belongs to the dog)

Words that end in S are the exception. The apostrophe should go after the S that is already there.

E.g. The octopus’ legs were wrapped around the seaweed (shows that the legs belong to the octopus)



Considering how similar the two words look and sound, it is no surprise that they are commonly misused. They actually have two slightly different meanings.

  • Affect is nearly always a verb

E.g. Mobile phones affect people’s attention spans

  • Effect is nearly always a noun

E.g. Mobile phones’ effects are also largely positive


Could/should/would of

This is a common mistake due to could’ve/should’ve/would’ve and could of/should of/would of sounding alike. When people write should of, what they really mean is should have or should’ve.

  • Incorrect: We could of gone there today.
  • Correct: We could’ve gone there today.



There/they’re/their are confusing because they sound exactly the same, but have different meanings. Words like this are called homophones.

  • There: used when referring to a place.

E.g. The restaurant is over there.

  • Their: indicates possession.

E.g. This is their piece of cake.

  • They’re: a contraction of the phrase they are.

E.g. They’re going to the cinema later.



Another two words that get confused because they sound the same, it can be easy to make mistakes with too and to. 

  • To: Commonly used before a noun or verb to describe a destination, recipient, or action.

E.g. My friend drove me to my appointment.(Destination)

I sent the address to my friend.(Recipient)

I'm going to get a cup of coffee.(Action)

  • Too: Used as an alternative to also or as well. It's also used to describe an adjective in extremes.

E.g. My friend listened out for the announcement too.

She, too, is a vegetarian.

It is too cold to go out today. 


I.e. / e.g.

These are commonly used interchangeably, but their uses are very different. 

  • I.e. means that is or in other words. It is from the Latin words id est.
  • E.g. means for example. It comes from the Latin words exempli gratia. 


We hope this has been a useful tool in your journey to perfecting your English grammar. Remember, everyone makes mistakes sometimes, even the best writers need to go back and proofread their work. If you’d like to read more about grammar, check out our previous blog post on English grammar rules to remember.

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