Common grammar mistakes in college essays
What are the most common grammar mistakes in college essays?
The most common grammar mistakes in college essays include comma splices, run-on sentences, subject-verb agreement errors, and misplaced modifiers. Students also frequently struggle with pronoun-antecedent agreement, incorrect apostrophe usage, and confusing homophones like affect versus effect. Eliminating these errors improves clarity, authority, and your overall grade.
Common mistakes vs. academic standards
Comparison table
| Dimension | Common Mistake | Academic Standard |
|---|---|---|
| Sentence Structure | Joining two thoughts with only a comma | Using semicolons or periods between independent clauses |
| Verb Usage | Mismatched subject and verb counts | Strict subject-verb agreement |
| Word Choice | Using informal or vague language | Precise, academic vocabulary |
| Punctuation | Misusing or omitting the Oxford comma | Consistent use of serial commas |
| Pronouns | Using 'they' for singular generic nouns | Using specific nouns or inclusive phrasing |
| Voice | Overusing passive voice | Prioritizing active, direct verbs |
Comma splices and run-on sentences
A comma splice occurs when you join two independent clauses with just a comma. A run-on sentence occurs when you join them with no punctuation at all. In academic writing, every independent clause must be separated by a period, a semicolon, or a comma paired with a coordinating conjunction (FANBOYS: for, and, nor, but, or, yet, so).
Subject-verb agreement
The subject and verb must always match in number. If the subject is singular, the verb must be singular. If the subject is plural, the verb must be plural. Errors often occur when 'intervening phrases' (words that come between the subject and the verb) confuse the writer about which noun is the actual subject.
Grammar mistakes applied: Before and after
Review these examples to see how common errors are corrected for a professional essay tone. **Comma Splice Fix** * **Incorrect:** The experiment failed, the temperature was too high. * **Correct:** The experiment failed because the temperature was too high. (Added a subordinating conjunction) **Subject-Verb Agreement Fix** * **Incorrect:** The list of requirements are long. * **Correct:** The list of requirements is long. (The subject is 'list,' which is singular) **Misplaced Modifier Fix** * **Incorrect:** After reading the book, the library closed. * **Correct:** After I read the book, the library closed. (The library did not read the book)
Tips for error-free writing
Use these strategies to catch mistakes before you submit your work:
- Check one thing at a time. Do one pass through your essay looking only for commas. Do a second pass looking only for verb tenses.
- Verify your pronouns. Every time you use 'it,' 'this,' or 'they,' ensure the reader knows exactly what noun you are referring to.
- Search for 'very' and 'really'. These are often filler words that signal weak vocabulary. Replace them with stronger, more precise adjectives.
- Watch your apostrophes. Remember that 'its' (possessive) does not have an apostrophe, while 'it's' (it is) always does.
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