Common Grammatical Errors and How to Avoid Them

Commonly Confused Words

Whether it’s because they look or sound the same, these commonly confused words can be easy for anybody to mix up. Get them sorted with these explanations.

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Their vs. they’re vs. there

• Their is a possessive pronoun used to describe something that belongs to a person or entity. They’re is a contraction of “they are.” And there is an adverb used to describe something in terms of space, place, or presence.
  • Example: Their visit begins tomorrow.
  • Example: They’re coming to see us tomorrow.
  • Example: There is a meeting on the schedule for tomorrow.
  • Example: We are going to have our meeting over there.

Your vs. you’re

• Your is a possessive pronoun used to describe something that belongs to the person you are speaking to, while you’re is simply a contraction of “you are.”
  • Example: Your phone is ringing.
  • Example: You’re a great communicator.

Then vs. Than

• Than is a comparative conjunction used to evaluate two associated things.
  • Example: “I like chocolate better than vanilla.”

• On the other hand, then is an adverb used to describe sequences in time or to mean “at a given time.”
  • Example: We ate dinner and then had dessert.
  • Example: Back then, things were different.

Its vs. It’s

• It’s is a contraction for “it is.” Though it might look like a possessive, its is the possessive form of the pronoun “it.”
  • Example: It’s raining.
  • Example: I saw its sharp teeth, and I ran away.

Whose vs. Who’s

• Similar to it’s vs. is, who’s is a contraction of “who is,” while whose is used to show possession.
  • Example: Who’s going to taking out the trash tonight?
  • Example: I don’t know whose chore that is.

i.e. vs. e.g.

• This one’s particularly tricky—especially if you haven’t been practicing your Latin skills. Use i.e., which is short for the Latin phrase id est, to mean “that is,” “specifically,” or “in other words.” Meanwhile, e.g., short for exempli gratia or “for the sake of an example,” should be used to say “for example.”
  • Example: I’ll need that sometime early next week, i.e., on Monday or Tuesday.
  • Example: I love many kinds of cheese, e.g., cheddar, provolone, and parmesan.

Affect vs. Effect

• “Effect” is commonly used incorrectly as a verb in place of “affected.” As a verb, effect means “to cause to come into being” or “to bring about often by surmounting obstacles.” Meanwhile, as a verb, affect means “to produce an effect upon someone or something.”
  • Example: They worked hard to effect change through government.
  • Example: That film had a profound effect on me.
  • Example: That film profoundly affected me.

Complement vs. Compliment

• A Compliment is when you express something nice to someone, and compliments denote kind wishes, a gift of some sort, or something free. On the other hand, as a noun, a complement is something makes another thing better or completes it, while as a verb, it describes the act of making another thing better or completing it.
  • Example: She complimented me on my new glasses.
  • Example: We enjoyed tiramisu, compliments of the chef.
  • Example: At the hotel, we ate a complimentary breakfast.
  • Example: Each having their own unique positive traits, they complemented each other nicely.
  • Example: That shirt complements the color of your eyes.
  • Example: You’ll want to choose a complementary side dish that pairs well with your main course.

Issues of Punctuation

En Dash vs. Em Dash

• Taking their names from the amount of space they take up on the page, these two dashes are commonly confused for each other, as well as for the even shorter hyphen. En-dashes (–) are used to mark ranges, most often numbers. Em-dashes (—) are used, much like a set of commas or parentheses, to separate information in a sentence—whether that’s to provide emphasis or additional detail. Meanwhile, hyphens, the shortest of the bunch, are used to connect and combine words.
  • Example of an en-dash: For tomorrow’s class, please read pages 1–25 in your textbook.
  • Example of an em-dash: For next week’s class, please read Moby Dick—all 135 chapters of it—and come prepared to discuss it.

Comma Splices

• A comma splice is when two independent clauses—parts of a sentence capable of standing on their own—are connected with a comma to create one single sentence. Comma splices can typically be fixed by changing the comma to a semicolon, separating the clauses into two distinct sentences, or adding conjunctions.
  • Example of a comma splice: Tomatoes are not vegetables, they contain seeds.
  • Correct example: Tomatoes are not vegetables; they contain seeds.
  • Correct example: Tomatoes are not vegetables. Actually, they are fruits because they contain seeds.
  • Correct example: Tomatoes are not vegetables because they contain seeds.

Issues of Clarity

While all these common grammar mistakes don’t always lead to writing that’s hard to understand, making the following errors can cause confusion for your readers.

Dangling Modifiers

• A modifier is a descriptive or clarifying word or phrase. A dangling modifier is what it’s called when it’s unclear what this word or phrase is describing or clarifying. For instance, in the example below, a reader could be confused about just who it is that’s going to school:
  • Example: I saw a dog on the way to school.
  • Correct example: On the way to school, I saw a cute dog.

Unclear Antecedents

• An antecedent is any noun that is referred to later by a pronoun. For example, in the above sentence, “Tomatoes are not vegetables because they contain seeds,” tomatoes is an antecedent later referred to by the pronoun they. Hence, an unclear antecedent is whenever it is not certain to what or whom a particular pronoun is referencing. In the sentence below, the pronoun she has an unclear antecedent.
  • Example: Rhonda bought Pauline lunch, and she was happy.
  • Correct example: Pauline was happy because Rhonda bought lunch for her.

It always helps to have illustrative examples of grammar issues and errors, as well as resources on hand to reference grammar basics as you go. Of course, even with lots of practice and study, even the most experienced writers will occasionally miss even the most basic of errors.

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