Common Grammar Mistakes (And 5 Tips to Avoid Them)

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common grammar mistakes and 5 tips to avoid them

Most common grammar mistakes might be small, but their impact is usually huge. It’s a matter of perception; what impression of you do the readers have after reading your mistake-ridden writing.

Do they think you’re uneducated? Someone who doesn’t pay attention to detail? A lazy writer who doesn’t respect the power of research?

Likely. That may be how the readers perceive you, or worse.

But even the best and educated writers commit a grammar mistake once in a while. That doesn’t make them boobs, they’re just honest mistakes (I believe).

I have compiled a list of some of these grammar mistakes. At the end of this post, I have given tips for you to avoid these mistakes.

1. They’re vs. Their vs. There

This is one of the most common mix-ups—the confusion between a contraction, a pronoun, and an adverb.

“They’re” is a contraction of “they are”; “their” is a pronoun, referring to something owned by a group, and “there” is an adverb referring to a place.

Usually, the mistake isn’t committed because one doesn’t know the difference among the three. They just slip by and find themselves in the wrong place at the wrong time.

they're vs their vs there
They’re vs. Their vs. There.

2. Its vs. It’s

Now here’s a confusion of a possessive pronoun “its” with a contraction of “it is”, “it’s.”

It is the “’s” in front of “it” in “it’s” that creates a muddle; that commonly means something is possessive, but not in this case—“it’s”, in this case, is just a contraction

3. Affect vs. Effect

The verb “affect” and the noun “effect” are actually related.

Maybe that’s why most people confuse them when they’re writing or talking about one thing having an impact on another.

“Affect” explains an action having an impact on something, and “effect” is the phenomenon that follows after.

“The loss of his mother affected him, greatly.”

“The loss of his mother had a profound effect on him.”

4. Your vs. You’re

you're vs your
The difference between ‘you’re’ and ‘your’.

For many English speakers around the world, these words are pronounced the same.

But one is a possessive pronoun, the other, a contraction.

“Your” implies that the subject owns something while “you’re” is a contraction of “you are” which indicates the subject is something:

“Your ride has arrived.”

“Honey… Hurry up! You’re going to be late!”

5. Dangling Modifiers

This is a mistake that usually eludes most average readers.

However, in some instances, they are so obvious and lead to misreading.

If a descriptive phrase fails to unambiguously qualify a noun or a verb, it becomes a dangling modifier.


Who even gave it that title?

Amanda Zantal-Wiener provided a good example of a dangling modifier.

After declining for months, Jean tried a new tactic to increase ROI.

In this sentence, the writer is trying to say that the ROI was declining, not Jean. Amanda then suggested a better way to write this sentence.

Jean tried a new tactic to increase ROI after it had been declining for months.

6. Comma splices

Comma splices are the most stealth grammatical mistakes. A comma splice happens when you have two independent clauses and you use a comma to join them.

We were tired, we took a rest.

The correct way of separating the two sentences as those above would be by use of a stronger punctuation mark other than the comma I just used—I could’ve used a semicolon, dash, or full stop; or use an appropriate coordinating conjunction.

We were tired. We took a rest.

We were tired, so we took a rest.

7. Subject-verb disagreement

This is another frequent source of error in writing.

Most people, even non-native English speakers, rarely commit errors when the grammatical subject is straightforward. Anyone with a basic command of English knows that the sentence, “my car are coming” is incorrect.

However, English in the real world is more complex than that sentence and subject–verb disagreements do creep into sentences unnoticed.

For example, look at this sentence:

The organization of the sports clubs have left a lot to be desired

subject verb disagreement
The organization of the sports clubs HAS left a lot to be desired.

Here, the writer is confused because he thinks that the plural noun “clubs” is the subject that has to agree with the verb “has/have” so the writer doesn’t notice that the grammatical subject is the singular noun organization.

8. Incomplete Comparisons

The following sentences don’t make sense when they’re said outside a comparative context.

“He is stronger.”


“She’s better”

Compared to who or what?

When such comparatives are used, make sure there’s clarity about what the subject is being compared to.

9. Me vs. I

Most people who have trouble with the interchangeableness of these two words actually give up trying and use whichever feels normal for them.

[Wrong] The report was emailed to Jane and I.

But the remedy is quite simple. If you remove Jane out of the sentence, you will see that the statement doesn’t sound right.

 [Wrong] The report was emailed to I.

That’s because the “I” needs to be replaced by its objective form, “me.”

10. To vs. Too

These are usually mixed up because most of us type faster than our brains’ processing speed.

It’s generally a case of an accidentally added “o” to “to” or an “o” dropped from “too” when writing hurriedly.

When you use “too” instead of “also” or “as well,” you should always use a comma (both before and after). Of course, when “too” comes at the end of a sentence, a period, not a comma should follow.

11.  i.e. vs. e.g.

I have to admit; I have used these terms interchangeably for a long time without knowing that they are actually different.

Most of us think that we can use either anytime we’re trying to flesh out a point or an idea. But this shouldn’t be the case, these two have different meanings and ought to be used in different contexts.

“i.e.” roughly translates to “that is” or “in other words,” and should be used to clarify a preceding point. On the other hand, “e.g.” stands for “example given” or “for example” and ought to illustrate the point by giving an example.

12. Compliment vs. Complement

subject verb disagreement 1
“Complement” means to complete, enhance, or make that thing/person perfect, while “compliment” means to furnish admiration for someone.

These two words are tricky; they are pronounced exactly the same, their spellings are only different because of a single letter, and are the same part of speech.

These things make them easily confusable.

But they have completely different meanings; to “complement” something or someone means to complete, enhance, or make that thing or person perfect; and to “compliment” someone is to praise or furnish admiration for someone.

For example:

He complimented me on my last mathematics paper.

Your new haircut complements your style.

13. En Dash vs. Em Dash

These are variants of the dash. The “–” is called the en dash, and “—” is one variant of the em dash.

Both of these dashes are used to represent a break in a sentence.

Their usage though can be very different: the en dash is also used to indicate range or differentiation, e.g., “The match will last for 45–50 minutes,” “There were 10-20 people.”

The em dash can be used to set off quotation sources.

14. First-come, First-serve

This idiom is actually a grammatical error. The idiom should be “served.” Not serve, otherwise the message says that the first person who arrives has to serve everyone that comes after, which doesn’t make sense.

15. Irregardless

Believe you me, this actually used to be a word. But it’s no longer accepted now, so it’s simply “regardless.”

The word still makes rounds on social media sites and is also the root of humorous debates between writers, but it seems to have been condemned to the gallows of literature.

16. Wet Your Appetite

It should actually be “Whet your appetite.” Whet means to sharpen or stimulate, so it is the appropriate word rather than wet which might imply dipping your appetite.

17. Make due

This idiom should be “Make do”. “Due” betrays the meaning of this idiom because it means “owed”.

So it’s appropriate to say “Make do” because now you’re saying that you’re going to get along with what you have.

18. All the sudden

When you want to write or say “all of a sudden” and “all of the sudden,” omitting “of” results in a grammatical error.

19. “Alot” vs. A lot vs. Allot

The first thing that you should know is that “alot” is not a word.

You might use it (on platforms where spellcheckers don’t exist), trying to say that some entity has a great deal of things. But the right word for that is “a lot.”

And then there’s “allot” which means any of the following: give, allow, portion, grant, assign, distribute, etc.

20. Less vs. Fewer

He will do it in 10 minutes or less.  Wrong.

You ought to use “less” for things that aren’t quantifiable e.g., less water.

Therefore, the first statement is wrong simply because minutes are quantifiable and as such, “fewer” being the right term for quantifiable things is also the right adjective for that sentence.

21. Title Capitalization

Different people apply different rules to title capitalization. Most people just capitalize the first word and Nouns which, I think, is the wrong way to go about it. Others just capitalize everything, and this— again—is incorrect.

Here are some of the recognized capitalization principles:

  • You should capitalize nouns, pronouns, adjectives, verbs, adverbs, and subordinate conjunctions.
  • Articles (“a,” “an,” “the”) should be lowercase
  • Coordinating conjunctions and prepositions should be lowercase.
  • Lowercase ‘to’ in an infinitive (“I want to play guitar”).

22. Between vs. Among

between vs among
Between vs. Among.

To simplify things, let’s just say:

One chooses between a coffee and tea, and chooses among all his trousers.

We use the word “between” when referring to two (or more) things which are distinctly separated. The word “among” is used when the things in context are part of a group or mass of objects.

23.  Could of Vs. Could Have

Statements like, “We could of lost our lives but the cop saved us” might sound the same as “We could have lost our lives but the cop saved us” when spoken but the use of “could of” instead of “could have” is never correct.

Because you can’t really tell the difference when either of the two is used in speech, this grammar error is simply a pronunciation issue which has spilled all over writing platforms, especially social media.

Tips to Help You Avoid Making Grammar Mistakes

1.Edit and proofread your writing

edit and proofread
Check for spelling mistakes, typos, formatting, and other errors.

This is the most significant way of avoiding grammar mistakes.

The mistakes are always going to be made, you can be sure about that.

Actually, your job is not to stop them from ending up in your first draft but stopping them from getting published or ending up in a submitted manuscript—your job description involves more damage control rather than prevention.

You should make sure that between completion of the first draft and submission, your piece goes through a couple of rounds of edits and proofreading.

You must check for spelling mistakes, typos, formatting, and other errors. You can edit and proofread on your or you can hire professionals to do a thorough job.

2. Form Simple Sentences

One of the most common rookie mistakes is thinking that if they craft complex sentences, their work is going to look legit.


It’s just a “Rookie Alert!”

Only seasoned writers can stitch a complex sentence and make it readable—well-trained writers possess the knowledge or tools used to make complex sentences read well and retain its intended message.

To avoid the ruckus created by long amateurish sentences, keep it simple, and write shorter sentences until you know more than the basics.

Some explanations are a bit complicated and only can only be elaborated using complex sentences; if this is the case, make sure that you’re cautious with your choice of words and always take a pause to reflect on the readability of the sentence.

3. Keep a Dictionary Handy

Use your dictionary to help you with spelling, pronunciation, grammar, and more.

Make sure that you check word meanings if you’re ambivalent about what the word in context stands for.

You can’t go around using words you know nothing about—that can be disastrous. So, before you use a new word or one whose meaning you are not sure of, look it up in your dictionary.

Buy one at the bookstore or download an app on your smartphone or laptop so that you can easily look up a new word, check its meaning, and explore contexts within which it can be used.

A dictionary also helps you ascertain whether the tense you used is correct or not. Plus, using a dictionary provides a good way to expand your vocabulary.

4. Don’t Rush

If you hurriedly handle a writing project, you’re probably going to end up with a lot of errors.

Yes, you want to publish as many blog posts as possible or send out as many cold emails as possible, but nobody wants to be on the other end reading cluttered, error-ridden blogs or proposals now, do they?

Always take your time and give each stage of your writing process ample time— there should be enough time for planning, writing, and editing.

If you don’t plan well enough, you’ll be freestyling a lot, and that just means a lot of errors and if after that rush, you don’t afford your editing step enough time, then most of the errors will end up in your published work or proposal email.

5. Use a Grammar Checker

As I said, proofreading is the most important way of making sure that grammatical mistakes and typos don’t end up in your published work.

I recommended either proofreading your work on your own or hiring a professional proofreader. If you opt for the former, the best way to go about it is by using software tools for grammar checking.

One such tool is Grammarly.

grammarly free
Grammarly helps writers compose mistake-free writing with its AI-powered writing assistant.

Not only will it check your text for grammar and spelling errors, but this tool also has a tone detector, a plagiarism checker, and vocabulary enhancement, among other significant features.

Over time, as you observe Grammarly flag and suggest solutions for different errors, you’ll learn a thing or two and improve your writing.


Maybe the mistakes on this list aren’t your pet peeves, but I’m sure you have some. My recommendation as always, is rigorous proofreading—with the help of professional proofreaders or software tools like Grammarly.

And, don’t rush. Remember, slow and steady wins the race.

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Jessica started off as an avid book reader. After reading one too many romance novels (really... is it ever really enough?), she decided to jump to the other side and started writing her own stories. She now shares what she has learned (the good and the not so good) here at When You Write, hoping she can inspire more up and coming wordsmiths to take the leap and share their own stories with the world.