Top 5 Grammar Mistakes Professionals Make and How to Avoid Them

In today’s globalized world, English is often the bridge connecting professionals across industries and within companies. Whether you’re writing emails, giving presentations, or leading meetings, polished grammar is crucial to convey professionalism and competence. Yet, even seasoned professionals occasionally stumble on common grammar mistakes, which can give the wrong impression. Below, we’ll highlight the top five errors and provide practical tips to avoid them.  

1. Mixing Up “Its” and “It’s”

This small punctuation mark trips up a great many people. If you want to show that you are attentive to detail and highly professional, making sure you correct these smaller mistakes is important.

- “Its” is possessive: *“The company increased its profits this quarter.”  

- “It’s” is a contraction for “it is” or “it has”: “It’s been a productive year.”  

How to Avoid:

Ask yourself if the phrase can be replaced with “it is” or “it has.” If yes, use “it’s.” Otherwise, go with “its.” Proofreading your emails and documents before sending them is important to catch these errors. 

2. Using Incorrect Verb Tenses

Confusion about past, present, and future tenses can make your sentences unclear. 

For example:  

- Incorrect: “Yesterday, I have completed the project.”

- Correct: “Yesterday, I completed the project.”

In this particular example, no one would be unsure about the meaning. However, in other cases, particularly in longer sentences which include details of an event, the selection of the correct verb tense is highly important, as mistakes can lead to serious misunderstandings.

How to Avoid:

Pay attention to time indicators in your sentences (e.g., “yesterday,” “next week”). Use a consistent tense for each context. If you’re unsure, tools like Grammarly or an online English tutor can help you improve your verb usage.  

3. Misplacing Modifiers

A misplaced modifier is a word or phrase that is awkwardly placed, causing confusion. 

For example:  

- Incorrect: “Running late, the meeting started without him.”

- Correct: “Running late, he arrived after the meeting had started.”

How to Avoid:

Ensure that the modifier (e.g., “running late”) is clearly linked to the correct subject. If something sounds off when you read it aloud, revise the sentence to clarify its meaning.  

4. Subject-Verb Agreement Errors

When the subject and verb don’t match in number, your sentence loses credibility. For example:  

- Incorrect: “The team are preparing the report.”  

- Correct: “The team is preparing the report.”

How to Avoid:

Identify the subject of your sentence (singular or plural) and make sure the verb matches. Pay special attention to collective nouns like “team” or “staff,” which are treated as singular in most cases.  

5. Overusing Commas

Using too many commas, or placing them incorrectly, can confuse readers. For example:  

- Incorrect: “The CEO announced, that we would expand.”  

- Correct: “The CEO announced that we would expand.”

How to Avoid:

Learn the basic rules of comma usage. Use commas to separate items in a list, after introductory phrases, and before conjunctions in compound sentences. When in doubt, simplify your sentence structure to reduce errors.  

Why Grammar Matters

Mistakes like these can affect how colleagues and clients perceive you. Clear, grammatically correct communication demonstrates attention to detail, builds trust, and helps you stand out in a competitive professional environment. Whilst smaller grammatical mistakes such as these might go unnoticed in speech, it definitely shows a lack of care and attention to detail in written correspondence and documents.

How We Can Help

At Precisa Classes, we specialize in helping professionals improve their English language skills, including grammar, through personalized online tutoring sessions. Our experienced tutors focus on common workplace scenarios—emails, reports, and presentations—so you can communicate with confidence.  

Ready to polish your English and boost your career? Book a free trial session today and see how we can help you avoid these mistakes while becoming a more effective communicator.