The 20 Most Common Student Errors

In 1993, Robert Connors and Andrea Lunsford published their results after studying the most common errors marked on 21,000 student essays. Generally, teachers consider syntactic or sentence-level errors (sentence fragments, fused sentences, comma splices) more serious than word-level errors (spelling, verb forms, agreement). The list below is ordered with most frequent errors first.

  1. Missing comma after an introductory element
  2. Vague pronoun reference
  3. Missing comma in a compound sentence
  4. Wrong word
  5. Missing comma(s) after a nonrestrictive element
  6. Wrong or missing verb ending
  7. Wrong or missing preposition
  8. Comma splice
  9. Missing or misplaced possessive apostrophe
  10. Unnecessary shift in tense
  11. Unnecessary shift in pronoun
  12. Sentence fragment
  13. Wrong tense or verb form
  14. Lack of agreement between subject and verb
  15. Missing comma in a series
  16. Lack of agreement between pronoun and antecedent
  17. Unnecessary comma(s) with a restrictive element
  18. Fused sentence
  19. Dangling or misplaced modifier
  20. Its/it's confusion
Connors, Robert J., and Andrea Lunsford. "Teachers' Rhetorical Comments on Student Papers." CCC 44 (1993): 200-23.