English grammar exercise with grammar cards on table showing common English grammar mistakes

Whether you’re learning English for the first time or you’re a seasoned speaker, grammar mistakes can be a persistent challenge. In professional settings, where clear communication is key, these errors can make a big difference in how you’re perceived.

English grammar is complex, with many rules and exceptions, making it easy to slip up. But don’t worry—understanding the most common mistakes and how to avoid them can significantly improve your language skills.

In this blog post, we’ll highlight the top 10 English grammar mistakes people make and provide tips on how to correct them. We’ll also dive into how improving your grammar can boost your professional credibility, whether you’re communicating with colleagues or clients.

1. Subject-Verb Agreement

One of the most common English grammar mistakes is related to subject-verb agreement. The verb in a sentence must agree with its subject in number (singular or plural). This seems straightforward but can get tricky, especially when the subject and verb are separated by other words.

  • Incorrect: The team of developers are meeting at noon.
  • Correct: The team of developers is meeting at noon.

Here, the subject “team” is singular, so the verb should also be singular.

Tip: Always identify the true subject of the sentence and make sure the verb agrees with it, not with any intervening words.

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2. Misplaced Modifiers

A modifier is a word or phrase that provides more information about another word in the sentence. A misplaced modifier can make your sentence confusing—or worse, completely alter its meaning.

  • Incorrect: Running quickly, the report was completed by Sarah.
  • Correct: Sarah, running quickly, completed the report.

In the first sentence, it seems like the report was running, which is not possible. The correct version clarifies that Sarah is the one running.

Tip: Place the modifier as close as possible to the word it modifies.

3. Comma Splices

A comma splice occurs when two independent clauses are joined by a comma without an appropriate conjunction or punctuation mark.

  • Incorrect: I finished the report, I sent it to my manager.
  • Correct: I finished the report, and I sent it to my manager.
  • Or: I finished the report; I sent it to my manager.

Tip: To fix a comma splice, use a conjunction (like “and” or “but”), a semicolon, or break the sentence into two distinct sentences.

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4. Using the Wrong Preposition

Prepositions can be tricky because their usage varies between languages and even regions where English is spoken. Words like “in,” “on,” and “at” may seem interchangeable, but they have specific uses.

  • Incorrect: He is good in math.
  • Correct: He is good at math.

Tip: If you’re unsure about which preposition to use, consult reliable grammar guides or language learning apps. Practice will also make preposition usage more intuitive.

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5. Confusing “Its” and “It’s”

The confusion between “its” (possessive) and “it’s” (contraction of “it is”) is incredibly common.

  • Incorrect: The company announced it’s new initiative.
  • Correct: The company announced its new initiative.

Tip: Remember that “it’s” always means “it is” or “it has.” If you can’t replace “it’s” with “it is,” then the possessive “its” is likely correct.

6. Overuse of Passive Voice

The passive voice occurs when the subject of the sentence is acted upon rather than doing the action. While passive voice isn’t technically incorrect, overusing it can make your writing seem weak or vague.

  • Incorrect: The meeting was attended by all employees.
  • Correct: All employees attended the meeting.

Tip: In business writing, use the active voice as much as possible for clearer, more direct communication.

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7. Wrong Word Choice

Sometimes, people confuse words that sound similar but have different meanings, known as homophones. This can lead to awkward or even embarrassing mistakes.

Commonly confused words:

  • Affect vs. Effect
  • There vs. Their vs. They’re
  • Compliment vs. Complement
  • Incorrect: The changes will compliment the company’s goals.
  • Correct: The changes will complement the company’s goals.

Tip: When in doubt, look up the word to ensure you’re using it correctly.

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8. Incorrect Use of Articles (“a,” “an,” “the”)

Using articles properly can be one of the most difficult aspects of learning English. Non-native speakers often struggle with when to use “a” or “an” versus “the.”

  • Incorrect: She is the expert in data analysis.
  • Correct: She is an expert in data analysis.

Tip: Use “a” or “an” when referring to something general and “the” when referring to something specific.

To explore more tips on mastering American English, check out our guide to learning American English slang.

9. Confusing Tenses

Verb tenses indicate when an action takes place—past, present, or future. Misusing tenses can confuse the reader or listener.

  • Incorrect: I was working on the project, and then my manager calls me.
  • Correct: I was working on the project, and then my manager called me.

Tip: Make sure your verb tenses are consistent throughout your sentence or paragraph. If you’re talking about the past, stay in the past unless there’s a clear reason to switch to another time frame.

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10. Double Negatives

A double negative occurs when two negative words are used in the same clause. This can create confusion because the two negatives cancel each other out, making the sentence positive.

  • Incorrect: I don’t have no time for that project.
  • Correct: I don’t have any time for that project.

Tip: Stick to one negative word per sentence to avoid confusion.

How to Avoid These Grammar Mistakes

Improving your grammar takes time, but the effort is well worth it. Here are some ways to ensure you minimize these mistakes in your everyday writing and speaking:

  1. Read and Listen Regularly: The more you expose yourself to well-written English, the more natural proper grammar will feel. Reading books, articles, or even watching TV shows in English can help. Check out our top podcasts for learning business English here.
  2. Practice Speaking: One of the most effective ways to improve your grammar is by practicing it in real-life situations. You can do this with a language partner, tutor, or by enrolling in a language training course. At Fluency Corp, we specialize in corporate language training that helps professionals become fluent in English in the shortest time possible. Learn more about our programs here.
  3. Use Grammar Tools: Tools like Grammarly and Hemingway Editor can be very helpful in spotting grammar mistakes. However, these tools are not infallible, so make sure to also learn the rules behind your errors.
  4. Write Often: Writing forces you to organize your thoughts and helps you identify areas where you struggle with grammar. Whether it’s writing emails, reports, or even journaling, the more you write, the better your grammar will become.

Master English Grammar with Fluency Corp

Mastering English grammar is no small feat, especially when it comes to the intricacies of business communication. From subject-verb agreement to confusing homophones, the errors we’ve discussed can make a big impact on how you’re perceived in professional settings.

Understanding these common grammar pitfalls and practicing ways to avoid them will greatly improve your fluency and confidence.

Ready to take your English skills to the next level? Fluency Corp offers tailored corporate language training to help you achieve just that. Whether you’re looking to brush up on your grammar or become fluent for professional reasons, we can help. Contact us today to learn more about our training programs!