10 Most Common Grammar Mistakes Writers Make (Fix Them with 2 Clicks)

Grammatical errors are the worst problem a writer can have. They chime in a piece without you notice it and then swiftly break your article, deeming it sloppy and unprofessional.

From all the grammar mistakes I often see writers make, there are a few that stand out from the rest.

(I will be honest and tell you I’ve also made some of these mistakes in the past, so believe me when I tell you these problems are commonplace.)

In this article, I will show you the ten most common grammar errors that writers make, plus how you can fix them in just two clicks with the help of one of my favorite writing tools.

Does that sound interesting to you? Then let’s jump right into it.

⚠️ Warning: This article is 5,068 words long. Download the summarized version with the exact steps to fix your grammar mistakes.

What Is a Grammatical Error?

A grammatical error is a concept used to describe a sentence that commits a faulty, uncommon, or controversial usage of grammar rules.

Since grammar defines the rules that structure a language, which in this case is English, violating these rules means the reader may not understand the full meaning of a given sentence.

Grammatical Error #1: Misplaced Commas

The comma is a basic element anyone who has ever written knows. Unfortunately, few writers seem to understand their proper use.

A comma, in the most basic sense, is a small break or a pause. Just like when you speak and you take a second to breathe or connect an idea in your mind, you use a comma to create that pause in your sentence.

As Roy Peter Clark, author of Writing Tools, puts it:

The comma may be the most versatile of marks and the one most closely associated with the writer’s voice. A well-placed comma points to where the writer would pause if he read the passage aloud.

There are multiple ways you use a comma, the most common being when you want to:

List attributes or actions

• e.g., “I like hamburgers, pizza, and chicken wings;” or
• “he’s smart, trustworthy, and independent.”

Connect independent clauses

• e.g., “he went to his house, and then he took a nap;” or
• “if she had told me that, I’d have not done it.”

Emphasize contrast

• e.g., “he was sweating, despite he was sitting on a chair.”

To make a small clarification

• e.g., “my friend, who I’ll call Johnny, is pretty cool.”

There are other uses of the comma, like when you use the “e.g.,” as I did before, or when you write a date, but in this case, I’m referring to the use in active sentences.

Because the nature of a comma is so personal—there are people who like to make a lot of pauses when they write while others like to explain ideas all at once—their use is often taken for granted.

The problem with commas is that writers seem to use them too lightly, sprinkling them too often in the wrong places. Writers either forget to use the comma when they should (which can include the Oxford comma) or they use it when it’s not necessary.

Here’s a list of the most common grammatical errors with commas I’ve seen and that you need to keep an eye on:

Noun and Verb

Whenever you construct a sentence that has a noun and a verb, they must be kept together. No comma should be put between both the subject and the verb, as that makes the copy look clunky.

Here’s an example with a grammatically incorrect sentence and one that’s correct.

Correct grammar: Keep your verbs and nouns together.

Two Nouns

Just as you can’t put a comma between a noun and a verb, you can’t put one between two nouns (unless you’re listing them, in which case you can).

Correct grammar: Never put a comma between two nouns unless it’s a list.

Two Verbs

Whenever a noun is tied with two verbs—like when a subject is doing two things at the same time—you must keep them together, without a comma interrupting the action. Not only this will look bad, it will also confuse the reader.

Correct grammar: Never put a comma between two verbs unless it’s a list.

Two Independent Clauses

Whenever you have two independent sentences (or clauses), you must keep them separated with a full stop or a semicolon, not with a comma. In some cases, you can make the sentences dependent by using a conjunction like “and” or “or.”

• Incorrect: The marketing team ran a meeting, Lynda missed it.
• Correct (with semicolon): The marketing team ran a meeting; Lynda missed it.
• Correct (with period): The marketing team ran a meeting. Lynda missed it.
• Correct (with conjunction): The marketing team ran a meeting and Lynda missed it.

Comparisons

Any comparison must be separated with a comma. In the grammatically incorrect sentence to the left, you can see the meaning isn’t clear. The one with the comma, instead, is much clearer in its meaning.

Correct grammar: Use a comma when comparing two ideas.

Conjunctions

Two conjunctions that always create confusion are the “and” and “but.” Here’s the simplest way I can put the use of commas in relation with these two conjunctions:

• If the sentences are independent, you can use a comma before these conjunctions.
• If the sentences depend on each other, you can’t use a comma before these conjunctions.

Here’s how this looks like:

Dependent Clauses

Example #1

• Incorrect: I write a lot, and I make a lot of money.
• Correct: I write a lot and I make a lot of money.

Example #2

• Incorrect: Mary is a great writer, but a bit stubborn.
• Correct: Mary is a great writer but a bit stubborn.

Independent Clauses

Example #1

• Incorrect: I like to write, and read.
• Correct: I like to write and read.

Example #2

• Incorrect: I love to write but it tires me.
• Correct: I love to write, but it tires me.

Being honest, I will tell you I get confused with these conjunctions and the way you use the commas. But if you practice a lot, you will get better, putting the commas in the right type of clause.

Should You Use the “Oxford Comma”?

The “Oxford Comma,” also known as the “serial comma” or the “Harvard comma,” is the comma you use after the last item in a list of three or more items, is a highly controversial topic in the world of writing.

(The fact that writers discuss over the use of a comma in a list clearly shows how interesting writers are, but that’s something for another discussion. 😅)

In the sentence, “the cat likes to eat tuna, insects, and rats,” the last comma (the one after “insects”) is the Oxford comma. A small animal, indeed, but one that breaks havoc the world of writers.

Many writers love the Oxford comma, while many others hate it. I could go on and on over the technical details of its use, but in reality, its use is entirely up to you.

In my case, I prefer to use the Oxford comma because I believe it makes my writing clearer and more precise. Avoiding to use the Oxford comma doesn’t make a sentence grammatically incorrect per se.

Some writers, like William Strunk Jr., author of The Elements of Style, believes you should use the Oxford comma:

In a series of three or more terms with a single conjunction, use a comma after each term except the last.

Other organizations, like The New York Times and Associated Press, believe you should never use it.

The only case where no writer would deny the use of the last comma is when its avoidance would cause confusion in the message, as in the following example:

Correct grammar: If you use the Oxford comma, add one after each listed element.

In the first case, you’d believe you’re using the two latter attributes as a way to describe his writing skills. In the latter, in contrast, you’re clarifying that these attributes refer to John’s personality, regardless of his writing.

Besides these specific cases, you can choose to adopt the Oxford comma or to avoid it altogether. Whatever your decision, don’t make a big fuss about it, will ya?

Grammatical Error #2: Where’s the Semicolon?

Semicolons are a weird monster that makes everyone uncomfortable. For some unknown reason, few people get their power right.

I know I’ve become in love with the semicolon—only a writing nerd can become in love of a semicolon 😜—after I realized how awesome it is.

Think about the semicolon as a punctuation mark more powerful than a comma, but not as serious as a full stop. It’s like you get a mix of both worlds, without having to compromise anything.

A semicolon is like a virgin piña colada, or a Saturday-night Uber ride home, or a diet coke, or…well, I think you get the picture.

The funniest explanation of the true nature of a semicolon comes from my favorite cartoon artist, The Oatmeal, who said:

The best part about using semicolons is that they’re incredibly easy to use.

The main usage for semicolons is when you have two independent clauses (remember that a clause is a fancy way of referring to a sentence) that you want to tie without having to resort into a comma or a full stop. It’s as simple as that.

Example #1

• Incorrect: Marketing and sales teams must work together, any company can benefit from that alignment.
• Correct: Marketing and sales teams must work together; any company can benefit from that alignment.

Example #2

• Incorrect: John loves to read nonfiction books. Maria prefers fiction. (This could be correct, but IMO the second sentence looks too strong in this context)
• Correct: John loves to read nonfiction books; Maria prefers fiction.

You can also use a semicolon when you want to make a list of objects (although I highly recommend you avoid this and use bullet points).

Next time you go around writing two independent sentences, use the semicolon. It will surprise how versatile it is and how much it improves your writing—you will also look like someone who knows how to write as most people don’t even know how to use one.

Grammatical Error #3: Wrong Parallelism

Sometime during your writing career, you will be faced with the decision of adding a parallel idea within a sentence. Let’s say you were writing the following sentence:

Basketball is one of America’s most popular sports.

After you wrote that sentence, you remember that a Canadian high school physical educator invented the game, and you think that idea would look great in that sentence.

You don’t want to add the sentence separately, however, as it would lose the point of your text; you just want to add it somewhere in that sentence. For that reason, you decide to write:

Basketball, which was invented by a Canadian called James Naismith, is one of America’s most popular sports.

The problem is that the new parallel sentence (“which was invented by a Canadian called James Naismith”) is too long to add between two commas.

You could use a parentheses, which also help with parallelisms, but honestly, they are mostly useless.

I believe parenthesis work like the footnote that you see in books, something that’s related to the idea but something that you can easily ignore. They work like an interesting blurb, nothing more.

Source

The best way to create useful parallelisms in your content is through the use of an em-dash (“—“). With an em-dash, you can nest one idea next to the other without interrupting the bigger one.

It’s a tragedy—a tragedy for writers, at least—that people prefer the use of parentheses or commas over the effortless power of an em-dash.

That is not to say parentheses or commas don’t have place in your sentences. Rather, they’re not the best tools you can use to create a parallelism.

A comma works when your parallelism is small. An em-dash, in contrast, is stronger—like when you put on the emergency brake in your car.

Did you see what I just did there? The comma was very small and subtle, while the em-dash develops a separate yet related sentence that extended the idea without missing the point of the former.

Whenever you want to create a parallel sentence, use an em-dash. You will make your writing much clearer and stronger without distracting people.

Em-dash vs. en-dash vs. hyphen

The em-dash isn’t the same as the en-dash (“–“) or the hyphen (“-“).

Yes, they’re just lines, but the conventions writers have created around them matter a lot.

Here’s how you can wrap yourself around these three lines:

• The em-dash separates entire ideas. It’s like a more powerful comma or semicolon.
• The en-dash, the black sheep of these lines, is used to separate words or ideas that are directly connected.
• The hyphen is used to connect compound nouns, verbs, and adjectives

Here are some examples to illustrate these ideas:

Em-dash

1. The man ran fast—as if he was a bullet train.
2. I know writers who are very smart—albeit a bit obnoxious—and also very funny.
3. I ate all the donuts—all 6 of them—and now I’m full.

En-dash

1. The match ended up 1 – 0.
2. You need to take the New York–Philadelphia bus.
3. We’re living in a post–modern world.

Hyphen

1. Nouns: It was an eye-opening experience.
2. Adjectives: He was not-so good looking.
3. Verbs: They were nickel-and-diming me.

Grammatical Error #4: Abuse of the Passive Voice

The passive voice has a bad rep among writers, and for some good reasons. The passive voice is boring and formal without adding much power to your sentences.

Did you see that? The second sentence comes with a punch that the former sentence lacks, even though it’s very similar in its content and structured with a passive voice.

The best rule of thumb any writer ever come around the use of passive voice comes from George Orwell, who once said: “Never use the passive where you can use the active.”

Source

Pretty clear the old George, amirite?

As you can see, you can use the passive voice, but only when you have no other option at hand.

When a sentence could make use of the active verb—that is, when the subject does something—then use it. Your readers will appreciate it, even if they don’t realize it.

If you are mindless about the use of the passive voice, your readers will feel like they’re trapped in wet sand—slowly dragged to the bottom of the article without them wanting to do it on their own.

Active Voice vs. Passive Voice

Example #1

• Incorrect: I was surprised by my friends.
• Correct: My friends surprised me.

Example #2

• Incorrect: Content is said to be an effective way to generate leads.
• Correct: Marketers say content is effective to generate leads.

Example #3

• Incorrect: Best Writing was founded by Tomas Laurinavicius.
• Correct: Tomas Laurinavicius founded Best Writing.

Whenever you write a sentence with the passive voice, go back immediately and rewrite it in the active voice. In the great majority of the cases, you will be able to make the switch without ruining the reading experience.

In some cases, however, it will make sense to use the passive voice. The passive voice, after all, exists in the case a subject receives the action of a given verb.

If you want to highlight the passive effect of the subject being done something to it, then it works just fine.

Take a look at the following example:

Correct grammar: Always use the active voice.

In the former example, the sentence looks clunky. Yo get the action and then you get the reason, which doesn’t look good. The latter case, while in the passive voice, looks much clearer—even dramatic.

As I said before, the passive voice does a wonderful job of highlighting emotions, and that example fits the idea perfectly.

You can also use it when the subject of the verb is unknown (like in the example above) or you are being openly generic. In any other case, the active voice will be your best bet, so use it.

Next time you write a passive sentence, rewrite it into the active form—unless you’re using it on purpose. 😉

Grammatical Error #5: Watch Out for the Homophones

When I writing this article, I checked what other bloggers have written on the improper use of grammar. The #1 grammar mistake they all talked about was the bad use of homophones. Since everyone since to be obsessed with homophones, I’ll briefly mention them in here.

To start, homophones are two or more words that have the same pronunciation but carry different meanings or spellings.

Some common homophones I see frequently misused are:

• Affect, effect
• Compliment, complement
• Farther, further, father
• Flair, flare
• Here, hear
• Knight, night
• Into, in to
• Its, it’s
• Lose, loose
• Made, maid
• Peak, peek, pique
• Resent, recent
• There, their, they’re
• To, too
• Where, were
• Who’s, whose
• Your, you’re

The bad use of homophones is common. Oftentimes, it happens due to a lack of attention to detail and bad editing. It’s still improper grammar, but not one that’s critical.

To solve this grammar error, you want to re-read everything you read twice: after you’ve finished the first draft, and before you publish your piece.

Also, you should use a grammar checker like Grammarly, as I will later explain, so you can find those mistakes in just a few clicks.

Grammatical Error #6: Be Careful with the Homographs

There will be times where you will write a piece of content which will have your readers think “what did he mean by that?”

Homographs, a close cousin to the homophone, are words that are spelled the same and which have different meanings. In some cases, these words may be pronounced the same.

Some of the most common homographs I’ve seen are:

• Attribute
• Bar
• Content
• Contact
• Contract
• Convert
• Effect
• Even
• Extract
• Impact
• Import
• Incline, inclined
• Leave
• Lose
• Notice
• Objective
• Record
• Refund
• Subject
• Suspect
• Tie

In most of these cases, the homograph has more than one way of pronouncing them, which dramatically changes its meaning.

For example, the sentence “the content was good” has two different meanings:

1. It could mean that a piece of content was good. In this case, the accent would go on the first syllable.
2. The sentence could refer (in a rather awkward fashion) to a feeling of satisfaction. In this case, the accent would go on the second syllable.

Both sentences are seemingly equal, yet they differentiate themselves by a large margin.

The use of homographs can destroy the meaning of a key phrase without you ever realizing it, even if you use a grammar checker.

The only solution I can suggest is that whenever you use any of the homographs above, make sure you’re being clear and specific in the way you word a sentence (like in that case, where “word” means “to express”).

If you can use another word to describe that homograph, then do it. If you’re in doubt, use Power Thesaurus to find a synonym for that word.

Grammatical Error #7: Abuse of Adverbs

Adverbs have a good reason to exist: they modify or qualify a verb, noun, or adjective, adding depth to your ideas.

Clearly, this is good. (See what I did there? 😬)

More often than not, however, adverbs shouldn’t be used.

There are three problems with adverbs:

1. They kill the descriptive qualities of a writer
2. They are redundant
3. They dilute the message of a sentence

Adverbs Problem #1: Lack of Originality

Adverbs are the best tool for the lazy writer; they make their writing less creative and detailed.

Take into consideration the following two sentences:

Correct grammar: Avoid using adverbs when you can use a more detailed explanation.

The former sentence is fine, but the description of the action (the speed on which the subject went to the store) is ambiguous. What does “rapidly” actually mean?

“In a rush,” on the other hand, gives me a more detailed explanation. I can imagine the face of the subject; I can feel his tension.

You can even take this example further by using an analogy, which would look like this:

“He went to the store as if it was the last thing he’d ever do.”

Most writers often hate adverbs, like Stephen King, who has been quite blunt with them:

The adverb is not your friend. With adverbs, the writer usually tells us he or she is afraid he/she isn’t expressing himself/herself clearly, that he or she is not getting the point or the picture across.

Source

In other words, whenever you can make a specific description of the way something is being done, use analogies and other literary devices, not adverbs.

Adverbs Problem #2: Redundant

Another problem with adverbs is that they can be misused in cases where they’re self-explanatory.

Take this example:

Correct grammar: Avoid using adverbs when you can use a more detailed explanation.

You can’t run slowly; if you did, you’d be jogging.

A good adverb you could use in that sentence could be:

“He happily ran to the store.”

You can run happily or sadly, and in either case, the adverb would correctly modify (i.e., describe) the verb. But running fast is obvious, so it’s unnecessary.

Roy Peter Clark, who has written in both fiction and nonfiction, recommends watching the adverbs whenever they’re not necessary:

At their best, adverbs spice up a verb or adjective. At their worst, they express a meaning already contained in it.

Adverbs Problem #3: Dilute the Message

Finally, an adverb makes the message contained within a sentence less powerful and clear.

Take these examples:

ADVERBS

In this case, the adverb isn’t wrong per se; rather, it could be taken away and the sentence would be just fine.

The idea that an adverb dilutes your message is similar to the previous one. If you’re trying to convey desperation, there are other ways to do so, before or after that sentence.

The adverb “desperately” doesn’t add much to the message, especially because we know the man was sad, an emotional state which can be tied to desperation.

Remember: adverbs are fine as long as they’re not killing your descriptive qualities, self-explanatory, or diluting your message.

Whenever you use an adverb, think whether you really need it. If you’re not sure, kill it. ☠️

Grammar Mistake #8: Prepositions at the End of Words

Prepositions are words that express “spatial or temporal relations” (in, under, towards, before) or that mark different “semantic roles” (of, for).

Some of the most commonly used prepositions (including phrasal instances) are:

• of
• in
• for
• on
• over
• to
• before
• from
• with

It’s well known among writers that prepositions should never go at the end of words. The rationale behind this idea is that it looks sloppy and unprofessional.

Correct grammar: Avoid using prepositions at the end of words, unless it’s done on purpose.

Unless your goal is to look colloquial and informal, you should always aim to use the prepositions before the end of sentences.

For example, instead of writing “people often forget why they work for,” you should write “people often for what reason they work.” The latter is both correct and looks much more professional.

Correct grammar: You can use prepositions at the end when otherwise would look too formal.

There will be cases, however, the correct use of prepositions will look a bit too formal. People aren’t used to hearing people use prepositions before the end of words, so writers become afraid if they use them correctly people will be turned off.

An example of such formality could be “the new employee explained the company from which he came.” It’s correct but it’s formal; I understand.

In such case, the only solution is to think about your audience and client. If the audience isn’t formal, you can use the informal and “incorrect” preposition. If the client also has an informal tone, then again, you can take the wrong route. Otherwise, I recommend you stick to using the prepositions before the end of words.

Make this a hard rule to follow, especially when you write for a large company whose audience is highly educated. The client will feel like you’re a real writer, one that takes your craft seriously, and not just a “blogger” who wants to make a few bucks writing online.

Grammatical Error #9: Don’t Dangle Those Modifiers

Writers often develop their content thinking as if the reader knows what they’re trying to say. This is a problem.

In that last sentence, the subject “this” could be the reader, the thing the writer is trying to say, or any other thing. “This,” in such case, is called a “dangling modifier.”

A dangling modifier is a word or phrase that modifies a previous sentence…when the reader isn’t sure the exact object the used modifier is trying to modify.

Writers use dangling modifiers all the time, without them realizing it (and that includes me). We get so caught up in our own ideas we forget the reader won’t necessarily follow each idea we write and thus will get lost in translation.

Dangling modifiers aren’t bad per se; rather they can be a problem if misused.

Take the following examples:

Correct grammar: Avoid using modifiers that modify a subject that’s not clear.

Sure, the second phrase after the semicolon explains the “this,” and such sentence structure would work colloquially. But when written, the reader has to wait until she reads the entire sentence to see the reason why that subject doesn’t go to concerts. It only takes the reader a second to read the phrase, but that second can be what bores the reader and makes her leave your article.

Some more subtle problems can be when a word is used to describe a given situation:

Correct grammar: Avoid using modifiers with passive voice.

Some other cases of badly used dangling modifiers can exist when you use a prepositional (e.g., “with a feeling of tiredness, the concert was enjoyed”) or participle phrase (e.g., “feeling tired, the concert was enjoyed”).

Whatever the case, the two simplest ways to fix the problem of dangling modifiers include:

• Adding the subject immediately after the modifier, like in the example above
• Making the sentence both active and with a simple “noun + verb” structure

My favorite solution is the latter, as it makes your writing much clearer and concise.

Whenever you see yourself using an introductory phrase that modifies the subject, make sure you’re not using a dangling modifier that doesn’t modify anything.

Grammatical Error #10: Wrong Use of Conjunctions

Conjunctions are those silly little words that show a local relationship between object, phrases, clauses, and sentences.

“Conjunction” seems like a big brainy word, but they’re some of the most commonly used words, including the following pairs:

• And / Or
• Not / But
• Either / or
• Neither / nor
• Both / and
• That

At first sight, you’d think the use of conjunctions is so basic that’s not necessary to go over them…but you’d be wrong.

The most common conjunctions mistakes come with the either, neither, both, and that combinations mentioned above.

Let’s take a look at each of them in detail:

Either/Or

The problem with the first combination of conjunctions—the either / or pair—is that writers use them to describe one or more than two objects, when they’re used to describe two and only two objects.

Correct grammar: Use the “either” conjunction with not more than two subjects.

Remember that the “either” conjunction goes next to two and only two objects; no less and no more.

Neither/Nor

The problem with the misuse of the neither / nor pair comes in different shapes, including:

1. When a writer uses either the “neither” or “nor” separately
2. They use them with one or more than two clauses
3. They use them to negate a sentence 😱

Here are some examples to illustrate these problems:

• Incorrect: I can neither eat pizza or hamburgers.
• Incorrect: I can’t neither eat pizza, hamburgers, nor bagels.
• Incorrect: I can’t neither eat pizza nor hamburgers.
• Correct: I can neither eat pizza nor hamburgers.

Remember that neither and nor go together when you negate something; if you use the “not” then you can’t use the “neither” conjunction.

Also, neither is the negative of either, so the same rules mentioned above for the latter apply for the former.

Both/And

The problem with conjunctions “both / and” is similar as in the previous two cases: writers use them with more than two clauses or mix “both” with the conjunction “or” (in such case, you’d use the “either” conjunction).

• Incorrect: I can both eat pizza, hamburgers, or bagels.
• Incorrect: I can eat both pizza or hamburgers.
• Correct: I can eat both pizza and hamburgers.

Remember that the “both” conjunction is positive and can only be used with not more than two objects.

That

The “that” conjunction is one of my favorite conjunctions. As a Spanish-native speaker, we use the equivalent of the “that” (“que”) all the time, so when I started learning English, I used the “that” conjunction all the time.

Anyway, the problem with the “that” is that the writer uses it when he shouldn’t, or he doesn’t use it when he should.

Correct grammar: Use the “that” conjunction with care, as it can be overstated.

While you could technically use the “that” in the incorrect sentence, it looks awful, so it’s best avoided.

The problem with conjunctions is subtle yet I see it happening more often than I’d like to, even in my own writing.

If you are trying to improve your writing, remember to get a good grasp of your conjunctions, even if that takes going back to your elementary grammar notebooks.

How to Fix All Your Grammar Mistakes

If you want to fix all your grammar mistakes once and for all, there’s one tool you can use: Grammarly.

With Grammarly, your only job is to copy and paste your content in its app—web or otherwise—and get the grammar fixes the tool automatically recommends.

Let’s take this article I wrote for Foundr:

I’d simply need to copy and paste the entire piece in Grammarly’s app. In the right column, I can see all the grammar mistakes Grammarly found.

The only task I have to do is to let Grammarly take me to each instance they found where there’s a mistake and fix it.

Obviously, Grammarly isn’t foolproof. Sometimes the grammar mistakes you make are on purpose (because, let’s say, you’re using slang or something like that) or it corrects something that doesn’t connect with your style.

You need to check each mistake closely, making sure the corrections are relevant.

At the end of the day, however, you will see Grammarly will save you hours of countless editing and make your writing pristine like a professional writer. For a full analysis of this tool, please check my Grammarly review.

Go to Grammarly today and check it out for free.

How to Write with No Grammar Errors

So here you have it: the 10 most common grammar mistakes writers make.

Next time you’re sitting down in front of your computer writing a piece for one of your clients, make sure to go over each of these points I mentioned here.

To make your life easier, I’ve developed a simple checklist with a summary of these 10 grammar errors so you can quickly go over them.

Sign up below and get it in your inbox.

🎁 Bonus: Download the article’s summarized version with the exact steps to fix your most common grammar errors.