10 Common English Grammar Mistakes ESL Students Make (and How to Fix Them)

Welcome, dedicated English learners and teachers! Mastering English grammar can feel like a complex journey, but focusing your efforts on correcting the most common English grammar mistakes is the fastest path to improving clarity and confidence. These are not minor issues; they are the high-impact areas that, once fixed, make your writing and speaking sound significantly more fluent and natural. Think of them as the foundational pillars of clear communication. Getting these right will make everything else you learn fall into place more easily.

This guide moves beyond a simple checklist of errors. We will dissect 10 frequent stumbling blocks that often challenge beginner to intermediate students. For each point, we will explore not just what is wrong, but also why these mistakes happen so frequently. This approach helps build a deeper understanding rather than just memorizing rules.

Inside, you will find:

• Clear correct-vs-incorrect examples to illustrate each point.
• Actionable tips and quick correction strategies you can apply immediately.
• Micro-practice exercises designed to reinforce your learning.
• Special teacher notes and activity suggestions for classroom integration.

Our goal is straightforward: to provide a practical resource that helps you identify and eliminate these persistent errors. By tackling these specific challenges head-on, you build a much stronger foundation. Let’s turn these common grammar hurdles into stepping stones toward true English proficiency.

1. Subject-Verb Agreement Errors

Subject-verb agreement is a foundational rule in English grammar: a singular subject needs a singular verb, and a plural subject needs a plural verb. This concept is one of the most common english grammar mistakes for learners, often because their native language may not require verbs to change form based on the subject's number. Mastering this skill is crucial for clear and correct sentence construction.

The confusion often arises when words come between the subject and the verb, or when the subject itself is tricky, like a collective noun or an indefinite pronoun.

Common Mismatches and Corrections

Let's look at some frequent errors and how to fix them.

• Incorrect: The list of items are on the desk.

• Correct: The list of items is on the desk. (The subject is "list," which is singular.)

• Incorrect: Each of the students have a book.

• Correct: Each of the students has a book. (Indefinite pronouns like "each" are always singular.)

• Incorrect: Neither the teacher nor the students is here.

• Correct: Neither the teacher nor the students are here. (When using 'or/nor,' the verb agrees with the subject closest to it: "students" is plural.)

Quick Tips for Agreement

1. Find the True Subject: Always identify the main subject of the sentence. Ignore any prepositional phrases (like "of the students" or "with all the dogs") that come between the subject and the verb.
2. Memorize Singular Pronouns: Words like each, every, either, neither, anyone, everyone, and somebody are always singular and require a singular verb.
3. Check "Or/Nor" Sentences: For subjects joined by "or" or "nor," match the verb to the noun or pronoun that is physically closer to it in the sentence.

For those looking for structured exercises, you can find excellent ESL grammar practice online that helps reinforce these core rules through repetition.

Teacher's Note: Create a "sentence surgery" activity. Write incorrect sentences on a whiteboard and have students work in pairs to "operate" on them by identifying the subject, finding the verb, and making them agree. This hands-on approach makes the grammar rule more memorable.

2. Common Homophone and Contraction Confusions (their/there/they're; its/it's)

Homophones are words that sound the same but have different meanings and spellings. These small words are a frequent source of common english grammar mistakes, especially when they involve contractions. The confusion between possessives (their, its) and contractions (they're, it's) is particularly widespread because the rules can feel inconsistent to a learner.

These errors often appear in writing because the distinction isn't audible in speech, and the spelling differences are subtle. Mastering these distinctions is a major step toward more polished and professional writing.

Common Mismatches and Corrections

Let's examine some of the most frequent mix-ups and their correct forms.

• Incorrect: The students put they're assignments over their.

• Correct: The students put their assignments over there. ("their" shows possession, "there" indicates a place.)

• Incorrect: Their happy about the results over there.

• Correct: They're happy about the results over there. ("They're" is a contraction of "they are.")

• Incorrect: The dog wagged it's tail.

• Correct: The dog wagged its tail. ("its" is the possessive form.)

• Incorrect: Its a beautiful day.

• Correct: It's a beautiful day. ("It's" is a contraction of "it is" or "it has.")

Quick Tips for Agreement

1. Run the Substitution Test: If you're unsure, try replacing the word with its full form. If "it is" or "they are" makes sense in the sentence, then you need the contraction (it's, they're). If not, you need the other form.
2. Memorize the Exception: In English, apostrophes often show possession (e.g., the cat's toy). However, possessive pronouns like its, his, her, their, and yours are the exception and never use an apostrophe. Remembering this single rule clears up most of the confusion.
3. Use Memory Tricks: Associate the words with their meanings. There has the word "here" in it, so it refers to a place. Their has an "e-i" like in "heir," someone who possesses things.

Building a strong vocabulary is key to avoiding these mix-ups, and you can find many resources for ESL vocabulary practice online to help distinguish between tricky words.

Teacher's Note: Create a "fill-in-the-blanks" worksheet with sentences missing their/there/they're or its/it's. Have students work in pairs to fill them in and then justify their choice by explaining whether it's a place, a possession, or a contraction. This forces them to articulate the rule.

3. Incorrect Use of Articles (A/An/The)

Articles are the small but mighty words (a, an, the) that specify whether a noun is general or specific. For many ESL learners, this is one of the most persistent common english grammar mistakes because their native languages, like Russian, Japanese, or Chinese, may not use articles at all. Mastering them is a huge step toward sounding more natural and fluent in English.

The difficulty comes from their complex rules, which depend on whether a noun is countable or uncountable, definite or indefinite, and singular or plural. These subtle errors can significantly impact how clearly your message is understood.

Common Mismatches and Corrections

Let’s examine some frequent article errors and how to fix them.

• Incorrect: I saw a beautiful sunset yesterday. Sunset was amazing.

• Correct: I saw a beautiful sunset yesterday. The sunset was amazing. (Use "the" because the listener now knows which specific sunset you mean.)

• Incorrect: I need an help with my homework.

• Correct: I need help with my homework. ("Help" is an uncountable noun and doesn't take "a" or "an.")

• Incorrect: She is studying the mathematics and the chemistry.

• Correct: She is studying mathematics and chemistry. (General academic subjects do not usually require an article.)

Quick Tips for Agreement

1. First Mention vs. Specific: Use a/an when you introduce a singular, countable noun for the first time. Use the when referring to that same noun again, or when the noun is specific and known to both the speaker and listener.
2. Countable vs. Uncountable: Before choosing an article, ask if the noun can be pluralized. Uncountable nouns (like advice, information, luggage, furniture) cannot be plural and do not use "a" or "an."
3. Generalizations: Avoid using "the" when making a general statement about a plural noun or an uncountable noun. For example, "I love music" (not "the music").

Teacher's Note: Create an "Article Auction." Give students a list of sentences with missing articles and some "money." They must "bid" on the correct article (a, an, the, or no article) for each sentence. This gamified approach makes learning the nuanced rules more engaging and competitive.

4. Confusion Between 'To,' 'Too,' and 'Two'

Homophones, words that sound the same but have different meanings, are a classic source of common english grammar mistakes. The trio of 'to,' 'too,' and 'two' is a prime example. Because they are pronounced identically or very similarly, learners often mix them up in writing, leading to sentences that can be confusing or nonsensical. Understanding their distinct roles is key to using them correctly.

'To' is a versatile word, most often used as a preposition indicating direction (e.g., "go to the store") or to form the infinitive of a verb (e.g., "to run"). 'Too' is an adverb that means 'also' or 'excessively.' Finally, 'two' is simply the number 2.

Common Mismatches and Corrections

Let's examine some frequent errors and see how to fix them.

• Incorrect: The two friends wanted too spend time together.

• Correct: The two friends wanted to spend time together. (Here, "to" is needed to form the infinitive verb "to spend.")

• Incorrect: I want to go there to. It's to cold.

• Correct: I want to go there too. It's too cold. ("Too" means "also" in the first part and "excessively" in the second.)

• Incorrect: She said I could come too, and bring my friend to.

• Correct: She said I could come too, and bring my friend too. (In both instances, the meaning is "also.")

Quick Tips for Agreement

1. Check the "O"s: Remember that too has an extra "o," just like it means something extra ('also') or an excessive amount ('too much').
2. Look for the "W": The number two has a 'w' in it. Think of 'w' as standing for 'word' or 'win,' helping to link it to the number.
3. Practice Substitution: If you can replace the word with "also" or "excessively" and the sentence still makes sense, the correct choice is too. If not, it's likely to.
4. Default to "To": When you need a preposition for direction or purpose, or are using the base form of a verb, to is almost always the correct choice.

Teacher's Note: Create a cloze (fill-in-the-blanks) worksheet with sentences missing 'to,' 'too,' or 'two.' Have students work in pairs to fill in the correct word and explain their reasoning for each choice. Discussing the logic out loud helps solidify the distinct uses of each word.

5. Incorrect Use of Run-On Sentences and Comma Splices

A run-on sentence occurs when two or more complete thoughts (independent clauses) are incorrectly joined without proper punctuation or a connecting word. A comma splice is a specific type of run-on where only a comma is used to connect these independent clauses. For many ESL learners, mastering sentence boundaries is a significant hurdle, making this one of the most common English grammar mistakes that can disrupt readability and clarity.

These errors often happen because students may not fully recognize where one complete idea ends and another begins, or they may be unsure how to use conjunctions and semicolons correctly. Learning to identify and fix these issues is essential for developing strong, coherent writing.

Common Mismatches and Corrections

Let's examine frequent run-on and comma splice errors and their solutions.

• Incorrect (Run-on): I studied hard I passed the test.

• Correct: I studied hard, and I passed the test. (Using a comma and conjunction.)

• Incorrect (Comma Splice): The weather was beautiful, we went to the park.

• Correct: The weather was beautiful, so we went to the park. (Using a comma and conjunction.)

• Incorrect (Comma Splice): The students completed their homework, they were proud of their work.

• Correct: The students completed their homework; they were proud of their work. (Using a semicolon to connect related clauses.)

Quick Tips for Agreement

1. Identify Independent Clauses: A complete thought or independent clause has both a subject and a verb. Practice identifying these units within longer sentences to spot potential run-ons.
2. Use the FANBOYS Test: You can correctly join two independent clauses with a comma followed by one of the FANBOYS conjunctions: For, And, Nor, But, Or, Yet, So.
3. Learn the Semicolon's Power: A semicolon (;) can be used by itself to connect two closely related independent clauses. It shows a stronger connection than a period but a weaker one than a conjunction.

For more focused activities on building better sentences, you can find excellent ESL writing practice online that includes sentence-combining exercises.

Teacher's Note: Create "sentence split" flashcards. Write a run-on sentence on one side of a card. In pairs, students must read the sentence and write down three correct ways to fix it on a small whiteboard: using a period, a semicolon, and a comma with a FANBOYS conjunction. This reinforces multiple correction strategies.

6. Misuse of Apostrophes (Beyond Possession and Contractions)

Apostrophes serve two primary functions in English: showing possession and forming contractions. However, their misuse, especially when creating plurals, is one of the most common english grammar mistakes for both ESL learners and native speakers. Incorrectly adding an apostrophe to a plural noun (like 'pen's' instead of 'pens') can create confusion and make writing appear less professional. Mastering apostrophe rules is a key step toward polished and accurate writing.

The confusion often happens because the rules for possession, contractions, and plurals can seem to overlap, particularly with words ending in 's'. Understanding when not to use an apostrophe is just as important as knowing when to use one.

Common Mismatches and Corrections

Let's look at some frequent errors and how to fix them.

• Incorrect: The student's are happy.

• Correct: The students are happy. (This is a simple plural, not a contraction or possession.)

• Incorrect: The dog wagged it's tail.

• Correct: The dog wagged its tail. ("It's" is a contraction for "it is," while "its" is the possessive pronoun.)

• Incorrect: She's studying for her test's.

• Correct: She's studying for her tests. ("Tests" is a plural noun, so no apostrophe is needed.)

• Incorrect: The book's cover is blue.

• Correct: The books' covers are blue. (If referring to multiple books, the apostrophe comes after the 's' to show plural possession.)

Quick Tips for Apostrophes

1. Run the Contraction Test: If you see an apostrophe, try to expand the word into two words (e.g., "it's" becomes "it is"). If the sentence no longer makes sense, the apostrophe is likely incorrect.
2. Ask the Possession Question: Ask yourself, "Does this noun own something?" If the answer is yes, an apostrophe is needed to show possession (e.g., the cat's toy). If not, it's probably just a plural.
3. Remember: Plurals Don't Need 'S: The most frequent error is adding an apostrophe to a simple plural. Unless the plural noun is possessive (like the students' books), it will almost never need an apostrophe.

Teacher's Note: Give students a short paragraph full of apostrophe errors. Have them act as "Punctuation Detectives," using highlighters to mark each incorrect apostrophe and then rewrite the paragraph correctly. This gamified approach makes identifying one of the most common english grammar mistakes more engaging.

7. Dangling and Misplaced Modifiers

Modifiers are words or phrases that describe other parts of a sentence. When they are not clearly connected to the word they are supposed to describe, they can create confusing or even humorous sentences. This is another one of the most common English grammar mistakes, as it requires a solid understanding of sentence structure and logical word order.

A dangling modifier describes a word that isn't actually in the sentence, while a misplaced modifier is simply too far away from the word it describes. Both errors can completely change the intended meaning of a statement.

Common Mismatches and Corrections

Let's look at some frequent errors and how to fix them.

• Incorrect (Dangling): Having finished the homework, the movie was enjoyable.

• Correct: Having finished the homework, the students enjoyed the movie. (The modifier "Having finished the homework" now correctly describes "the students.")

• Incorrect (Misplaced): The hikers saw a bear on the trail with cameras.

• Correct: The hikers with cameras saw a bear on the trail. (Placing "with cameras" next to "hikers" clarifies who has the cameras, not the bear.)

• Incorrect (Dangling): Walking down the street, the rain started falling.

• Correct: As I walked down the street, the rain started falling. (The sentence now includes the person who was "walking down the street.")

Quick Tips for Agreement

1. Ask "Who?" or "What?": After reading the opening phrase or modifier, ask "Who or what is doing this action?" The answer should be the subject that immediately follows the comma.
2. Keep Modifiers Close: Place descriptive words and phrases as near as possible to the nouns they are modifying. A good rule is to keep them right next to each other.
3. Reveal the Subject: If a modifier is dangling, you often need to rewrite the sentence to add the correct subject. This might involve changing the modifier into a full clause (e.g., "Walking..." becomes "As I walked...").

Teacher's Note: Hand out sentences with misplaced modifiers. Give students scissors and have them physically cut the sentences apart and rearrange the words and phrases into an order that makes logical sense. This kinesthetic activity helps reinforce the concept of proper word placement.

8. Tense Inconsistency and Incorrect Tense Usage

Verb tense signals when an action happens (past, present, or future) and whether it is ongoing or complete. Tense inconsistency is one of the most jarring common english grammar mistakes, occurring when a writer shifts between tenses without a clear, logical reason. This error disrupts the flow of a story or explanation, leaving the reader confused about the timeline of events.

The difficulty for ESL learners often stems from how their native language expresses time, as some English tenses may not have a direct equivalent. Mastering tense consistency is essential for producing clear, professional, and easy-to-understand writing.

Common Mismatches and Corrections

Let's examine some frequent tense errors and how to correct them.

• Incorrect: She walked to the store and buys groceries.

• Correct: She walked to the store and bought groceries. (Both actions happened in the past, so both verbs should be in the past tense.)

• Incorrect: The character goes to the castle. He was tired and sits down.

• Correct: The character goes to the castle. He is tired and sits down. (This maintains a consistent present-tense narrative.)

• Incorrect: By next year, I will study here for three years.

• Correct: By next year, I will have studied here for three years. (The future perfect tense is needed to show an action that will be completed by a specific point in the future.)

Quick Tips for Tense Consistency

1. Establish a Main Tense: Before you start writing, decide on the primary tense for your narrative (usually simple past for stories or simple present for analyses) and stick with it.
2. Use Tense Timelines: Draw a simple timeline to visualize the relationship between different actions. This helps clarify whether an action happened before, during, or after another, guiding your choice of tense.
3. Master Time Clauses: Remember that in clauses beginning with words like when, before, after, or as soon as, you should use the present tense to refer to a future event (e.g., "I will call you when I arrive," not "when I will arrive").

For learners seeking a structured way to practice, The Kingdom of English offers lessons on 60 grammar topics, including extensive coverage of verb tenses to build a solid foundation.

Teacher's Note: Give students a short paragraph written with inconsistent tenses. Ask them to become "Time Detectives." Their mission is to highlight all the verbs, identify the main narrative tense, and correct any verbs that don't belong on that timeline. This turns a grammar exercise into a fun, focused puzzle.

9. Incorrect Pronoun-Antecedent Agreement

Pronoun-antecedent agreement means a pronoun (like he, she, it, they) must match the noun it replaces (the antecedent) in both number (singular/plural) and gender. This is one of the more complex common english grammar mistakes because it involves tracking connections between words, often across a sentence. The rule becomes especially tricky with indefinite pronouns and the modern use of the singular "they."

The challenge for ESL learners often stems from their native language's pronoun system, which may not have gendered pronouns or may handle singular and plural agreement differently. Mastering this ensures sentences are logical and unambiguous.

Common Mismatches and Corrections

Let's examine some frequent pronoun-antecedent errors and their solutions.

• Incorrect: Each student should bring their own lunch. (Traditional rule)

• Correct: Each student should bring his or her own lunch. (Or, in modern usage, "their" is now widely accepted as a singular pronoun.)

• Incorrect: The company celebrated their success.

• Correct: The company celebrated its success. (In American English, collective nouns like "company" are singular.)

• Incorrect: Someone left there bag on the chair.

• Correct: Someone left their bag on the chair. (The antecedent "someone" is singular, and "their" is the correct possessive pronoun.)

• Incorrect: Neither the dog nor the cats finished its food.

• Correct: Neither the dog nor the cats finished their food. (Like with verbs, the pronoun should agree with the antecedent closest to it: "cats" is plural.)

Quick Tips for Agreement

1. Identify the Antecedent: Before choosing a pronoun, find the specific noun it refers to. Is that noun singular or plural? Male, female, or neuter?
2. Use Connection Lines: When practicing, physically draw a line from the pronoun back to its antecedent to check for a match in number and gender.
3. Address Singular 'They': Teach students that while "his or her" is traditionally correct for singular antecedents like "everyone," the singular "they" is now common and accepted for inclusivity or when gender is unknown.
4. Practice Substitution: If you're unsure, try replacing the pronoun with the antecedent noun. For example, in "The team lost their game," replacing "their" with "the team" ("the team game") feels less natural than "the team's game" ("its game").

Teacher's Note: Create a matching game with two sets of cards: one with sentences containing antecedents (e.g., "The boy," "The students," "Everyone") and another with corresponding pronouns ("his," "their," "their/his or her"). Students must match the correct pronoun card to each antecedent sentence, explaining their choice.

10. Confusion with Prepositions (In/On/At, For/During/While)

Prepositions are small words that indicate relationships between other words in a sentence, often specifying location, time, or direction. For many learners, prepositions are one of the most persistent and common english grammar mistakes because their usage is highly idiomatic. Unlike many grammar rules that follow a clear logic, prepositions often must be memorized as part of fixed phrases.

The logic for using a preposition in one language rarely translates directly to English, leading to frequent errors. The subtle differences between prepositions like in, on, and at for time and place, or for, during, and while for duration, can be especially challenging.

Common Mismatches and Corrections

Let's look at some frequent errors with these tricky words and how to fix them.

• Incorrect: The book is in the table.

• Correct: The book is on the table. (Use "on" for a surface.)

• Incorrect: I arrived in the airport at 3 PM.

• Correct: I arrived at the airport at 3 PM. (Use "at" for specific points or locations.)

• Incorrect: She studied during the exam.

• Correct: She studied for the exam. ("During" means something happened within a period, while "for" states the purpose or goal.)

• Incorrect: I'm good for math.

• Correct: I'm good at math. ("Good at" is a fixed collocation.)

Quick Tips for Prepositions

1. Learn in Chunks: Don't just memorize the word "at." Memorize phrases like at school, at the corner, at noon. Treating these as vocabulary chunks makes them easier to recall correctly.
2. Visualize the Concepts: For spatial prepositions, use diagrams. Draw a box to show what in means, a line for on, and a dot for at. Visual aids can make abstract rules concrete.
3. Focus on Common Collocations: Pay special attention to common verb+preposition or adjective+preposition pairings like listen to, wait for, interested in, and proud of.

Teacher's Note: Play "Preposition Charades." Give a student a card with a prepositional phrase like "under the table" or "on the chair." They must act it out without speaking, and the class has to guess the correct phrase. This activity connects the physical meaning to the word itself.

10 Common English Grammar Errors Compared

Turn Your Knowledge into Action with Consistent Practice

Navigating the intricacies of English grammar is a journey of continuous learning and refinement. Throughout this guide, we've dissected ten of the most frequent hurdles that learners encounter, from the foundational challenge of subject-verb agreement to the subtle nuances of prepositions and pronoun agreement. Recognizing these pitfalls is the crucial first step, but the real transformation happens when that awareness turns into consistent, deliberate action.

Remember, the goal isn't immediate perfection. Even native speakers misplace modifiers or create the occasional run-on sentence. The objective is to build a strong internal editor, a grammatical instinct that allows you to spot and correct these issues with increasing speed and confidence. Each mistake is not a failure but an opportunity for targeted improvement.

Key Takeaways for Lasting Improvement

As you move forward, keep these core principles at the forefront of your learning or teaching strategy:

• Isolate and Conquer: Don't try to fix everything at once. If tense inconsistency is a major issue for you or your students, dedicate a week to focusing solely on that. Use the micro-exercises from this article, find targeted drills, and pay special attention to verb tenses in everything you read and write.
• Active Application is Everything: Passive knowledge of grammar rules is not enough. The true test is applying them correctly under pressure. This means writing regularly, speaking often, and actively seeking feedback. Turn the correction process into a positive learning loop rather than a discouraging critique.
• Contextualize Your Practice: Learning grammar rules in a vacuum can be tedious and ineffective. Always connect the dots back to real-world communication. How does correct article usage make your meaning clearer? How does proper pronoun agreement prevent confusion for your reader? This connection provides the "why" behind the "what," making the rules stick.

Your Actionable Next Steps

Mastering the concepts we've explored requires a commitment to a structured and engaging practice routine. Simply rereading the rules won't build fluency. Instead, you need a system that reinforces learning through repetition and immediate feedback. Identifying and correcting common English grammar mistakes is a skill, and like any skill, it sharpens with the right kind of exercise.

You have now built a solid foundation of understanding. The next phase is to put that knowledge into practice consistently. For educators and tutors, this means finding resources that can provide structured, engaging, and trackable assignments. For independent learners, it means seeking out tools that make practice less of a chore and more of an interactive challenge. The path to grammatical precision is paved with daily, focused effort. Every sentence you write and correct is another step toward clear, effective, and confident communication.

For teachers and tutors looking to transform this knowledge into measurable student progress, The Kingdom of English provides a gamified platform built to tackle these exact challenges. Our system offers over 60 grammar topics with interactive exercises and AI-powered feedback, allowing you to assign targeted practice on the common English grammar mistakes discussed here. See student improvement in real-time by signing up for a free trial at The Kingdom of English.