grammar mistakes featured image 1

It happens to the best of us.

A spelling mistake in the subject line, a missing word in the last paragraph, an autocorrect gone wrong.

While a typo every once in a while probably won’t be enough to turn people off from your business for good, it won’t escape the notice of some of your most scrupulous readers.

To be sure your business is always making a good impression, here are some common grammar mistakes to steer clear of.

P.S. We left a couple grammatical errors in this blog post…can you point them out? Let us know what you see in the comments!

Commonly misused words

1. Affect/effect

The most important thing to remember is that affect is usually a verb and effect typically appears as a noun. While affect refers to the action of changing or influencing something, the change or result that occurs is the effect.


  • The candidate’s speech affected the audience positively.
  • The effect was that many voted for her in the election the next day.

Tip: Effect is also, less commonly, used as a verb when referring to a bringing about a change or an accomplishment.

Here’s an example for this usage:

  • Once elected, she effected new policies to make improvements for stakeholders.

2. Peek/peak/pique

Imagine you own a bakery and are having a one-day sale on specialty cupcakes. To promote the sale, you send your audience a photo the day before as a sneak peek to pique their interest. The photo is of a cupcake tower with a red velvet cupcake at the peak.

See the differences? The word peek is used to mean a quick look, whereas pique will signify a stimulation or provocation of some kind, and peak will refer to a highpoint.


  • Catherine peeked into the bakery to see what flavors were available.
  • A chocolate cupcake with peanut butter frosting piqued her appetitive.
  • At the peak time of day the bakery sold five dozen cupcakes in an hour.

3. Complement/compliment

To complement something means to complete or accompany something else well. You may have products that perfectly complement the services you offer.

A compliment, on the other hand, is a flattering remark. Like when a customer compliments your newest arrivals.


  • The shop’s new summer shawls complement this season’s sundresses.
  • After buying the shawl, Michelle received many compliments from her coworkers.

4. Further/ farther

This distinction is a simple one: farther refers to physical distance, and further relates to extension or degree.


  • Our agency will help your further your business by getting you in front of a larger audience.
  • We’ll make sure you’re going beyond your local community and reaching clients farther away on a national scale.

5. Then/than

Then is commonly used to designate the sequence of events: You wake up in the morning, then you leave for work. Than is used to compare two things: Your commute is shorter than your partner’s.


  • She posted the picture to Facebook then scheduled it to post on Twitter the next day.
  • The picture received more engagement than the plain text post.

6. Should of, could of, would of, must of

Avoid using these word combinations, and instead utilize the grammatically correct contractions should’ve, could’ve, would’ve, and must’ve. Or, simply break the contraction apart to two full words: should have, could have, etc.


  • They could’ve stayed at the spa all day.
  • Tim would have stayed longer if he had not had to pick up his children from school.


7. Commas

Commas are some of the most common punctuation in the English language. They are used to indicate a brief pause in a sentence. You can use commas to separate phrases within a sentence, or to break apart items in a list.

While most comma usage will be pretty intuitive, a misplaced or neglected comma has the power to seriously alter a sentence’s meaning. One of the most common examples is: “Let’s eat, grandpa!” versus “Let’s eat grandpa!” Notice the difference?

Despite some strict rules, there is some flexibility with comma usage. One example is the Oxford (or serial) comma. This refers to the comma right before the final item in a list of three or more terms. It’s grammatically correct to use this comma or leave it out — just be consistent with your choice.


  • All trips to Europe, Asia, and South America have vaccination requirements.
  • Before your trip, you must send in proper documentation.

8. Colons and semicolons

While colons and semicolons are sometimes used interchangeably, each has its specific function. A colon should start with a complete sentence, and then follow with a list or explanation. A semicolon will join two phrases that are related, and could stand on their own as complete ideas.


  • The IT company had three main values: put the customer first, deliver an unforgettable experience, and invest in innovation.
  • No two customers received the same guidance; each proposal was custom-created based on the client’s unique needs.

9. Apostrophes

Apostrophes are often overused or misplaced. Make sure you’re only using apostrophes in two scenarios: to indicate possession or to stand in for omitted letters.

A common mistake is express a period of time or plurality with an apostrophe — such as the 1920’s. While phrases that omit letters (such as “the roaring ‘20s”) or show possession (like “1920’s fashion trends”) are correct, if you are solely referring to a period of time, do so by adding an –s. For example, “The 1920s was a decade heavily influenced by jazz music.”

Another thing to avoid is using apostrophes with possessive nouns. These include yours, theirs, hers, his, and its. These already show possession, so there’s no need to add a –‘s.

Remember that it’s will only refer to a contraction for “it is.” If you want show possession (like in the phrase “its best feature”), be sure to leave out the apostrophe to avoid confusion.

You also need to make sure your apostrophe placement is right. When showing possession, if the noun is singular, you’ll usually add –‘s to the end of the word. If the noun is plural and already ends in –s, simply tack on an apostrophe. Lastly, if the noun is plural but does not end with an –s, add an –‘s.


  • He picked up his boss’s lunch order at 1 o’ clock.
  • The store was known for its homemade gelato.
  • Both his coworkers’ favorite gelato flavor was butterscotch.

10. Hyphen/en dash/em dash

Mistakes with these dashes are probably so common because they’re hard to tell apart.

Here’s a quick refresher: the hyphen is the shortest ( -), the en dash is a little longer (– ), and the em dash is the longest (— ).

Use hyphens for compound words, like nine-year-old cat. Additionally, when you use two words to describe a noun (known as a compound adjective), you can add a hyphen between these two words to make your meaning clear. You only need the hyphen when the compound adjective is before the noun.

Be careful with your hyphens because they have the ability to change meaning substantially. Consider the difference between twenty five-hour shifts and twenty-five hour shifts.

En dashes will only be used to show ranges, such as page numbers or dates.

Em dashes are used to break up long sentences and tack on more information.


  • Anita was a well-known chiropractor in her community.
  • She had attended Yale University from 1990–1994.
  • Her clients knew she could fix any ailment — whether they were suffering from back pain, neck pain, or tension headaches.

Sentence structure

11. Parallelism

Parallelism means that related elements of a sentence should match in word structure. So if you are using a list to drive a point home, make sure all the items are in parallel structure.


  • Correct: Making a donation will promote student development, increase literacy, and provide important leadership skills.
  • Incorrect: Making a donation will promote student development, increase literacy, and we will also be giving them leadership skills.

12. Subject/verb agreement

With each sentence you write, you want to make sure the subject and verb match — meaning singular subjects should be accompanied by singular verbs and plural subjects should be matched with plural verbs. The subject is the person or thing doing the action, and the verb is the action.

The tricky part is that some indefinite pronouns like everyone, someone, and anyone are always singular.


  • Correct: She has entered the photo contest.
  • Correct: They have all entered the photo contest.
  • Correct: Everyone has entered the photo contest.
  • Incorrect: Someone have entered the photo contest.

The golden grammar rule

No matter how much you study up on grammar, you’ll find exceptions that don’t hold true to the rules. It’s also important to remember that grammar can also change over time, and breaking a few rules for stylistic reasons isn’t always a bad thing.

Get the basics down and stay consistent with stylistic choices. For example, if you decide to use the Oxford comma in your writing, make sure it appears in everything you send or publish.

Here’s a cheat sheet to help you remember some of the key takeaways:

We left a couple grammatical errors in this blog post…can you point them out? Let us know what you see in the comments. Or tell us about any grammar mistakes you often notice.

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