This guide walks you through the 10 most frequent grammar mistakes, why they happen, and exactly how to fix them.<\/p>\n

Table of Contents<\/p>\n

Why Do Grammar Mistakes Happen So Often?<\/a>
- Mistake 1: Are You Confusing “There,” “Their,” and “They’re”?<\/a><\/li>
- Mistake 2: Do You Know When to Use “Your” vs. “You’re”?<\/a><\/li>
- Mistake 3: Is Subject-Verb Agreement Tripping You Up?<\/a><\/li>
- Mistake 4: Are You Misusing Apostrophes?<\/a><\/li>
- Mistake 5: Do You Know the Difference Between “Who” and “Whom”?<\/a><\/li>
- Mistake 6: Are You Running Sentences Together Without a Break?<\/a><\/li>
- Mistake 7: What Is a Comma Splice and Are You Making It?<\/a><\/li>
- Mistake 8: Are You Using “Less” and “Fewer” Correctly?<\/a><\/li>
- Mistake 9: Do You Confuse “Affect” and “Effect”?<\/a><\/li>
- Mistake 10: Are You Ending Sentences with a Preposition When You Should Not?<\/a><\/li><\/ul><\/li>
- How Do You Build a Habit of Catching These Mistakes?<\/a><\/li><\/ul><\/nav><\/div>\n
  <\/span>Why Do Grammar Mistakes Happen So Often?<\/span><\/h2>\n
  Most grammar errors are not a sign of poor intelligence. They are a sign of speed. Writers often focus on ideas and let the mechanics’ slip.<\/p>\n
  - Homophones (their\/there\/they’re) trip up even experienced writers because spell-check does not flag them.<\/li>\n<\/ul>\n
    <\/span>Mistake 1: Are You Confusing “There,” “Their,” and “They’re”?<\/span><\/h3>\n
    These three words sound identical but mean completely different things. Mixing them up is one of the most spotted errors in academic and professional writing.<\/p>\n
    \n
    “There” refers to a place: “The report is over there.”<\/li>\n
    “Their” shows possession: “Their research was thorough.”<\/li>\n
    “They’re” is a contraction of “they are”: “They’re presenting next week.”<\/li>\n<\/ul>\n
    <\/span>Mistake 2: Do You Know When to Use “Your” vs. “You’re”?<\/span><\/h3>\n
    “Your” shows ownership. “You’re” short for “you are.”<\/p>\n
    \n
    Example (wrong): “Your going to need to revise this section.”<\/li>\n
    Example (right): “You’re going to need to revise this section.”<\/li>\n<\/ul>\n
    <\/span>Mistake 3: Is Subject-Verb Agreement Tripping You Up?<\/span><\/h3>\n
    \n
    The subject and verb in a sentence must match in number.<\/li>\n
    A singular subject takes a singular verb.<\/li>\n
    A plural subject takes a plural verb.<\/li>\n
    The mistake appears most often when phrases come between the subject and verb.<\/li>\n<\/ul>\n
    Example (wrong): “The list of errors are long.”
    \nExample (right): “The list of errors is long.”<\/p>\n
    <\/span>Mistake 4: Are You Misusing Apostrophes?<\/span><\/h3>\n
    Apostrophes serve two purposes: they show possession and mark contractions.<\/p>\n
    \n
    Wrong: “The professor’s reviewed the paper’s.” (apostrophe in a simple plural)<\/li>\n
    Right: “The professors reviewed the papers.”<\/li>\n
    Right: “The professor’s feedback was detailed.” (possession)<\/li>\n<\/ul>\n
    <\/span>Mistake 5: Do You Know the Difference Between “Who” and “Whom”?<\/span><\/h3>\n
    “Who” is a subject pronoun. “Whom” is an object pronoun.<\/p>\n
    Trick: Substitute “him” or “her” in the sentence. If it fits, use “whom.” If “he” or “she” fits better, use “who.”<\/p>\n
    \n
    “Who wrote the report?” (He wrote it. So “who” is correct.)<\/li>\n
    “To whom should I address the letter?” (Address it to him. So “whom” is correct.)<\/li>\n<\/ul>\n
    <\/span>Mistake 6: Are You Running Sentences Together Without a Break?<\/span><\/h3>\n
    A run-on sentence joins two independent clauses without proper punctuation or a connecting word.<\/p>\n
    It forces the reader to do extra work to find where one idea ends and the next begins.<\/p>\n
    \n
    Example (wrong): “The deadline is Friday the team needs to submit the draft by Thursday.”<\/li>\n
    Example (right): “The deadline is Friday. The team needs to submit the draft by Thursday.”<\/li>\n<\/ul>\n
    <\/span>Mistake 7: What Is a Comma Splice and Are You Making It?<\/span><\/h3>\n
    A comma splice happens when you join two complete sentences with only a comma. It is a specific type of run-on that writers often miss because the comma makes the sentence look correct at a glance.<\/p>\n
    \n
    Example (wrong): “She submitted the assignment; it was three days late.”<\/li>\n
    Example (right): “She submitted the assignment, but it was three days late.”<\/li>\n<\/ul>\n
    <\/span>Mistake 8: Are You Using “Less” and “Fewer” Correctly?<\/span><\/h3>\n
    “Fewer” applies to things you count. “Less” applies to things you measure.<\/p>\n
    \n
    Wrong: “There were less errors in the final draft.”<\/li>\n
    Right: “There were fewer errors in the final draft.”<\/li>\n
    Right: “There was less confusion after the revision.” (confusion is not countable)<\/li>\n<\/ul>\n
    <\/span>Mistake 9: Do You Confuse “Affect” and “Effect”?<\/span><\/h3>\n
    “Affect” is almost always a verb. “Effect” is almost always a noun.<\/p>\n
    \n
    “The feedback affected her writing.” (verb, something acted on something else)<\/li>\n
    “The feedback had a noticeable effect on her writing.” (noun, the result of something)<\/li>\n<\/ul>\n
    <\/span>Mistake 10: Are You Ending Sentences with a Preposition When You Should Not?<\/span><\/h3>\n
    Ending a sentence with a preposition (“with,” “on,” “at,” “for”) is accepted in casual writing.<\/p>\n
    In formal academic or professional work, it often needs restructuring.<\/p>\n
    \n
    Casual: “This is the rule I was referring to.”<\/li>\n
    Formal: “This is the rule to which I was referring.”<\/li>\n<\/ul>\n
    <\/span>How Do You Build a Habit of Catching These Mistakes?<\/span><\/h2>\n
    The fastest way to reduce grammar errors is to slow down during the review stage.<\/p>\n
    Most writers spend 90% of their time writing and almost none editing. That ratio needs to change.<\/p>\n
    \n
    Leave a gap between writing and editing so you read what is actually on the page.<\/li>\n
    Use Trinka’s free grammar checker<\/a> as your final pass. It is built specifically for academic and professional writing and flags subject-verb disagreements, misused articles, and punctuation errors that generic tools miss.<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"
    Spot and fix the 10 most common grammar mistakes in your writing. Learn simple rules and use Trinka’s free grammar checker to write error-free.<\/p>\n","protected":false},"author":3,"featured_media":5924,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[173,208],"tags":[],"acf":[],"featured_image_url":"https:\/\/www.trinka.ai\/blog\/wp-content\/uploads\/2025\/12\/Trinka-Blog-Banner-750-\u00d7-430-px-45.png","_links":{"self":[{"href":"https:\/\/www.trinka.ai\/blog\/wp-json\/wp\/v2\/posts\/5923"}],"collection":[{"href":"https:\/\/www.trinka.ai\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.trinka.ai\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.trinka.ai\/blog\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.trinka.ai\/blog\/wp-json\/wp\/v2\/comments?post=5923"}],"version-history":[{"count":6,"href":"https:\/\/www.trinka.ai\/blog\/wp-json\/wp\/v2\/posts\/5923\/revisions"}],"predecessor-version":[{"id":6858,"href":"https:\/\/www.trinka.ai\/blog\/wp-json\/wp\/v2\/posts\/5923\/revisions\/6858"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.trinka.ai\/blog\/wp-json\/wp\/v2\/media\/5924"}],"wp:attachment":[{"href":"https:\/\/www.trinka.ai\/blog\/wp-json\/wp\/v2\/media?parent=5923"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.trinka.ai\/blog\/wp-json\/wp\/v2\/categories?post=5923"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.trinka.ai\/blog\/wp-json\/wp\/v2\/tags?post=5923"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}