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10 Common Grammar Mistakes To Avoid While Writing

What is one common grammar mistake writers should avoid while writing?

To help content writers and business professionals with avoiding common grammar mistakes, we asked content editors and marketing specialists this question for their best tips. From avoiding wordiness to avoiding faulty subject-verb agreement, there are several grammar mistakes that you can be mindful of that may help you write more clearly and with fewer errors for years to come.

Here are ten common grammar mistakes to avoid while writing:

  • Mixing up There/Their/They’re

  • Deciding Who vs That

  • Using Passive Voice

  • Mixing up I.E and E.G.

  • Avoid Wordiness

  • Placing Commas Incorrectly

  • Writing Run-on Sentences

  • Confusing Homophones

  • Incorrect Use of Affect/Effect

  • Avoid Faulty Subject-Verb Agreement

Mixing Up There/Their/They’re

The incorrect use of the words "there," "their," and "they're" is a common grammatical error. As homophones, they are pronounced the same but have different meanings. "There" denotes a location. "Their" refers to ownership of an object by a group. "They're" is a contraction for the words "they are." Stuart Hall's Mastery Philosophy empowers our students to excel in core subjects such as English to prepare for college’s academic rigors and avoid grammar errors such as these through a wide range of Advanced Placement courses to help our students.

Sharon Arne, Stuart Hall School

Common Grammar Mistakes To Avoid While Writing

Deciding Who vs. That

In a world where branding is everything and companies relentlessly try to humanize their business, I see, more often than not, companies refer to their organization as “who”. For example: The Phoenix-based company who provides tree trimming services. A good rule of thumb is to use “who” for people, and use “that” for objects — like a company! It’s a small detail that eagle-eyed readers appreciate when done correctly.

Desiree Cunningham, Markitors

Using Passive Voice

One of the most common writing mistakes is the use of the passive voice. It's not technically grammatically wrong but too many passive sentences can cause readers to feel disconnected from what they're reading. Try to avoid the overuse of "is/was" when drafting sentences.

Fred Gerantabee, Foster Grant

Common Grammar Mistakes To Avoid While Writing

Mixing up I.E and E.G.

I.e. is an abbreviation of the Latin phrase id est, which roughly translates to "that is" or "namely." It's used to clarify the previous statement: "All staff are paid the same starting rate, i.e., $15 per hour." E.g. is an abbreviation of the Latin phrase exempli gratia and means "for example." It's used to list one or more examples following a statement: "I love fuzzy critters, e.g., cats, dogs, and squirrels." It's easy to remember which is which by thinking of "e.g." as "egg," which sounds like the first part of the word "example."

Avoid Wordiness

One common grammar mistake writers should avoid when writing is wordiness. Inflating sentences with unnecessary words can confuse readers and lower the overall quality of your writing. Also, try to avoid overusing words such as “that”, “very”, and “just”. These words often act as filler which will not benefit your writing.

Greg Hannley, Soba Recovery

Placing Commas Incorrectly

Comma splices happen when two independent clauses are incorrectly joined together with a comma. One of the best ways to correct comma splices is to create two separate sentences. You can also correct a comma splice by inserting a coordinating conjunction like for, and, or, or but.

Randi Shinder, SBLA

Common Grammar Mistakes To Avoid While Writing

Writing Run-on Sentences

Every writer should avoid run-on sentences. A run-on sentence happens when two complete sentences are squashed together without using a coordinating conjunction or correct punctuation. This makes your writing look amateur and can be confusing for the reader.

Tim Mitchum, WinPro Pet

Confusing Homophones

The English language is full of homophones (words which sound the same but have different meanings and spellings). You may use common ones every day without thinking about it, like 'right' and 'write'. But others that you use less often might not come so naturally: 'principal' and 'principle', 'compliment' and 'complement'. If in doubt, take a moment to look up the correct spelling for the word you need. That small effort will make a much better impression on your client or your readers.

Amanda Napitu, Dentaly

Common Grammar Mistakes To Avoid While Writing

Incorrect Use of Affect/Effect

A lot of writers mistake affect and effect. They use the two in the wrong context. Effect is a change that results when something is done. Affect is the verb. The two get confused and misused. Make sure to know the difference when writing and using the two.

Jason Wong, Doe Lashes

Avoid Faulty Subject-Verb Agreement

All writers need to be consistent with their subject-verb agreements. It's very easy to miss these, but it's so important for ensuring proper grammar. For example, a singular subject (i.e., pizza) needs a singular verb (is): "This pizza is great!" The same goes for plural subjects: "Pizza and burgers are the best!"

Tom Mumford, Undergrads

Common Grammar Mistakes To Avoid While Writing

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