Common Writing Errors to Avoid at All Costs

As a reader, nothing pulls me out of a story faster than a glaring error. And I’m not talking about split infinitives or sentences that start with “But” — almost every novel published today breaks these “rules.” However, there are plenty of actual mistakes around word choice, spelling, punctuation, and grammar that really do jar readers. 

Let’s take a look at some of the most common writing errors (and how to correct them).

Incorrect words

Using the wrong word for whatever reason is a definite red flag for readers. I’m not going to insult you by explaining the difference between “your” and “you’re” or “there,” “their,” and “they’re,” but I am going to talk about some other word pairs that writers often mix up.

“Less” vs. “fewer” 

These are both antonyms of “more,” but they’re not interchangeable. Use “fewer” for items you can count, such as plates, coins, and chocolate bars. Use “less” for things you can’t count, like love, money, or salt.

✔️ I’m trying to eat fewer chocolate bars and less salt.

“I” vs. “me”

Most native English speakers use “I” and “me” correctly in isolation. Yet, people tend to forget the rule when combining the pronoun with “you.” Remember: only use “I” when you are one of the people doing the verb. If the verb is being done to, for, with, or without you, use “me.” Lastly, remember that “you” should always come before “I” (and before “me” in formal writing).

✔️ You and I should watch a musical together. 

✔️ The tickets belong to you and me.

📽️ In the media

In the musical Guys and Dolls, showgirl Miss Adelaide sings, “Doesn’t that kind of apply to you and I?” Missionary Sarah corrects her with, “You and me.”

“Effect” vs. “affect”

In the majority of cases, “effect” is a noun and “affect” is a verb.

✔️ Eating too many sweets negatively affects your teeth. 

✔️ What is the effect of eating too many sweets?

However, the exceptions can trip you up. “Effect” is a verb when used in the context of “effecting change,” while “affect” as a noun is a psychology term for the outward expression of emotion. For more details and tips on how to remember which spelling to use, check out this full guide.

“That” vs. “which” 

When it comes to introducing relative clauses, a lot of English speakers can’t tell you the rule for whether to use “that” or “which” — even if they can apply it correctly. 

Fortunately, the rule is simple (and consistent!). Use “that” to introduce restrictive information, i.e., anything that is essential to the meaning of the sentence. Use “which” to introduce other, nonrestrictive information.

✔️ The café that Jo recommended was great.

If you remove “that Jo recommended”, it’s unclear which café you’re talking about, so “Jo recommended” is restrictive information.

✔️ Dottie’s Café, which Jo recommended, was great.

If you remove “which Jo recommended”, it’s still clear which café you’re talking about, so “Jo recommended” is nonrestrictive information.

Note that in UK English, you can use “which” in the place of “that” (but you can’t ever use “that” in the place of “which”).

These are just some of the many words that writers sometimes mix up. For more examples, browse Cambridge Dictionary’s list of easily confused words. Keep a note of the word pairs that you often confuse and remember to check for them when you’re rewriting a draft.

Inconsistent language variations

Another common writing error is to use multiple dialect variations within the same text. This is acceptable in dialogue or written correspondence between characters from different regions, but the main narration should always stick to one regional variation.

❌ I realised the baby’s diaper needed to be changed.

✔️ I realized the baby’s diaper needed to be changed. (US)

✔️ I realised the baby’s nappy needed to be changed. (UK)

Here are the most common spelling differences between US and UK English:

And here is a list of some common vocabulary differences:

There are, of course, many more words that differ between US and UK English. Plus, other regions like Canada, Australia, and India have their own regional vocabulary too. If you’re not 100% sure on the correct word or spelling for your language variation, be sure to look it up!

Punctuation errors

Punctuation errors are not only jarring, but can accidentally change the meaning of a sentence. Gyles Brandreth illustrates this nicely in the title of his book Have You Eaten Grandma?

Commas

Commas are seriously abused in English (I blame the school system!). Of the numerous comma rules out there, we’ll look at the ones that writers get wrong most often.

Comma splicing

I pride myself on my good English, but even I am sometimes guilty of comma splicing in casual text messages. However, if you’re writing for publication, it’s essential to avoid the habit of using a comma instead of a period, semicolon, or conjunction.

❌ I like sitcoms, they make me laugh.

✔️ I like sitcoms. They make me laugh.

✔️ I like sitcoms; they make me laugh.

✔️ I like sitcoms because they make me laugh.

Remember: a comma should never be the only thing separating two sentences that can technically each stand alone.

Lists

Your school probably did teach you to separate items in a list with commas. And in general, that’s right. But there is an exception! When listing adjectives before a noun, only use commas if the order of the adjectives doesn’t matter. If the sentence sounds weird when you swap the adjectives around, don’t use commas.

✔️ the cute little boy

Because “little” modifies the noun more closely and “little cute boy” is not a natural phrase, there must not be any commas.

✔️ the polite, kind boy

You could just as easily say “the kind, polite boy”, so commas are needed.

You also might have heard of the Oxford comma. This is a comma before the “and” that precedes the final item in a list. It’s not always necessary, but sometimes it is, and it’s never wrong — so why not always use it?

❌ I admire my parents, Greta Thunberg and Albert Einstein.

This sentence could be interpreted to mean that my parents are Greta Thunberg and Albert Einstein. For clarity, we need to add a comma.

✔️ I admire my parents, Greta Thunberg, and Albert Einstein.

If you decide not to adopt a blanket-use policy, make sure you only use the Oxford comma when it clarifies the meaning of the sentence. Some people love the Oxford comma and some people hate it, but both parties will agree it’s worst of all to apply it inconsistently!

Restrictive and nonrestrictive information

Remember the difference between “that” and “which”? A similar principle applies to commas. Use commas to separate nonrestrictive information from the main clause; don’t use commas around restrictive information.

You can see this rule in practice in the previous examples about the café. But the rule also extends to information that is not preceded by “that” or “which.”

✔️ My neighbor Jane is the friendliest of my neighbors.

“Jane” is restrictive information because the sentence is meaningless without it.

✔️ My wife, Jane, is a pilot.

We don’t have to know Jane’s name to understand the sentence, so “Jane” is nonrestrictive information.

Named addressees

The above rule doesn’t apply when the restrictive information is the name of the addressee. Even though the name is necessary for listeners to determine which of them you are speaking to, you still need a comma before and/or after the addressee.

✔️ Sophie, where are you?

✔️ Why don’t you, Sophie, sit next to you, Charlotte?

Forgetting the comma is what leads to hilarious sentences like “Have you eaten Grandma?”

Hyphens

Hyphens are another punctuation mark that people regularly misuse. Here’s a quick run-down of the rules.

In general, you should hyphenate compound modifiers that come before the noun, but not those that come after.

✔️ That’s an over-the-counter medication.

✔️ You can get that medication over the counter.

However, never use hyphens with adverbs that end in “-ly” or with proper nouns, even when they come before the noun.

❌ What a beautifully-written sentence.

❌ He’s a New-York resident.

Moreover, don’t use a hyphen to indicate a pause in a sentence. Instead, use an em-dash (—).

❌ The restaurant was packed - pretty impressive for a Tuesday.

✔️ The restaurant was packed — pretty impressive for a Tuesday.

Apostrophes

I’m sure you already know the main uses of apostrophes: to indicate possession (“Harry’s”) and omitted letters from a contraction (“don’t”) — but not plurals. However, there are some instances where it’s not obvious how to form the possessive, and there is one exceptional case in which an apostrophe is used to form the plural after all.

Possessives with words ending in “s”

When you use a possessive apostrophe with a word ending in an “s,” you might not know whether to add another “s” or not. Unfortunately, there is no universal answer. “James’” is the convention in AP style, while “James’s” is preferred in MLA and APA styles. If you’re using a particular style guide, look it up — if you aren’t, just choose one and stick to it.

Possessives with two or more people

If two or more people are joint owners of one thing, just use an apostrophe after the last person. If each person owns their own separate item, use an apostrophe after each.

✔️ Nancy and Bill’s restaurant

Nancy and Bill jointly own a restaurant, so we only use one apostrophe.

✔️ Nancy’s and Bill’s restaurants

Nancy and Bill each own a different restaurant, so we use two apostrophes.

Plural letters

When (and only when) you are dealing with individual lower-case letters, use an apostrophe before the “s” to form the plural. 

✔️ Remember to dot your i’s and cross your t’s.

Punctuation with quotation marks

Punctuation gets a whole lot tricker when quotation marks are involved. It’s important to be aware that some rules differ depending on whether you’re using US or UK English.

US English only

When using US English, put commas and periods inside the quotation marks, even if they aren’t part of the quotation.

✔️ My favorite words are “penultimate,” “acquiesce,” and “cartography.”

✔️ She said, “You’re so immature.”

UK English only

When adopting UK English, put commas and periods (or “full stops,” as the Brits call them) outside the quotation marks unless the quotation is a full sentence.

✔️ My favorite words are “penultimate”, “acquiesce”, and “cartography”.

✔️ She said, “You’re so immature.”

US and UK English

In both variations, put colons and semicolons outside the quotation marks.

✔️ She said I was “immature”; I’ll get her back by spreading rumors behind her back.

Put question and exclamation marks inside the quotation marks if they are part of the quotation and outside the quotation marks if they are not.

✔️ Why did she say I was “immature”?

✔️ She said, “You’re so immature!”

Grammar mistakes

While poor punctuation doesn't usually obscure the meaning entirely, some grammar mistakes can make a sentence indecipherable (see “squinting modifiers” below). Make sure you avoid these common grammatical errors:

Poor subject and verb agreement 

Proficient English speakers almost always make the verb agree with the subject without even thinking: “I am,” “you are,” “he plays,” etc. However, there are some less intuitive cases where even experienced writers second-guess themselves. Here are a few of them.

Singular collective nouns

Some nouns that refer to more than one thing are nevertheless grammatically singular. Examples include: “family,” “team,” “club,” “audience,” “class,” “group,” and “orchestra.” These nouns should technically go with a singular verb form — although in UK English in particular, it’s becoming increasingly common to use a plural verb form when emphasizing individual members.

✔️ My family is visiting.

✔️ My family have their birthdays in June and July.

Alternative: the members of my family have their birthdays in June and July.

“There is” vs. “there are”

Even more confusing than collective nouns is the rule for “there is” and “there are” when there are multiple items listed. The general consensus among grammarians is that “there are” is pedantically correct, but “there is” sounds better in actual usage when the first noun in the list is singular.

✔️ There is a kitchen, a bedroom, and a living room in my flat.

✔️ There are two bedrooms, a kitchen, and a living room in my flat.

My advice is to avoid “there is” and “there are” as much as possible (after all, they’re wordy and vague anyway).

✔️My flat has a kitchen, a bedroom, and a living room.

Misplaced modifiers

A modifier is something that adds additional information to or limits the scope of a sentence. There are three common types of error regarding the placement of modifiers.

Dangling modifiers

A dangling modifier is one that doesn’t modify the right subject.

❌ Having spent hours tidying up, my friends cancelled on me last minute.

“Having spent hours tidying up” modifies “my friends,” but the speaker means for it to modify “me.”

✔️ Having spent hours tidying up, I was annoyed when my friends cancelled on me last minute.

One solution is to reword the sentence so that “I” is next to the modifier.

✔️ After I’d spent hours tidying up, my friends cancelled on me last minute.

Another solution is to turn the modifier into a clause with “I” as the subject.

Squinting modifiers

A squinting modifier is one whose referent is ambiguous.

❌ Running quickly exhausts me.

Does running exhaust me quickly, or is it running quickly that exhausts me? The following two sentences clear it up one way or the other.

✔️ I get exhausted quickly when I run.

✔️ I get exhausted when I run quickly.

Modifiers that shouldn’t be modifiers

Some modifiers are more restrictive than intended and shouldn’t be used as modifiers at all.

❌ I bought another cat named Ripple.

This implies that I now own multiple cats all named Ripple.

✔️ I bought another cat and named her Ripple.

Instead of a modifier, we need to add a new clause.

Inconsistent tense

One of the most jarring errors of all is switching tense mid-paragraph — or worse, mid-sentence. 

❌ Yesterday, I hadn’t even heard of Middlesbrough, let alone think I would be visiting the next day.

“Think” should be “thought” because it happened (or rather, didn’t) yesterday.

Switching tense mid-book is acceptable — as long as there’s a good reason for it and you signal the switch clearly.

📚 In literature

The Thursday Murder Club by Richard Osman is mostly written in the present tense. However, some chapters are Joyce’s diary entries and are written in the past tense. This is clearly marked by the word “Joyce” at the start of each chapter.

Incorrect past tense

By far the most common tense error in English is using the wrong past tense. Use the simple past (“I played,” “I ate”) when you’re talking about a completed action that no longer has a direct bearing on the present. 

✔️ I went on holiday to Spain.

Use a form of “have” and the past participle for incomplete actions or actions that have a result in the present.

✔️ I’ve been to Spain three times.

I might go to Spain again in my lifetime, so the action is incomplete. (Note: if you’re talking about someone who has died, you should say they “went” to Spain three times, as the action is complete.)

✔️ I’ve lost my phone.

My phone is still lost in the present.

I know it can be confusing to get your head around the difference, so here are two shortcuts to help you out: 

• If you can stick a specific time phrase into the sentence, use the simple past.
• If you can add “already,” “only,” “just,” “never,” or “not yet” without making a nonsensical sentence, use the past participle.

✔️ I went on holiday to Spain last month.

✔️ I’ve only been to Spain three times.

✔️ I’ve never lost my phone.

You should never use the simple past with “have”.

❌ I have ate.

✔️ I have eaten.

Regular verbs have the same simple past and past participle, both formed by adding “-ed.” For irregular verbs, you have to learn the simple past and the past participle. Here are some common examples of irregular verbs where the simple past and the past participle are different:

Keep an eye out for these errors and your accuracy should improve. Unfortunately, error-free writing doesn’t automatically equate to good writing. Once you’re confident you can write correctly, check out our tips on improving clarity to level up your writing further.