The twenty most common errors in college writing were identified by Andrea Lunsford and Robert Connors in research examining thousands of student essays in the late 1980s. Explanations of the errors have been adapted from The Everyday Writer by Lunsford and Connors (New York: St. Martin’s Press, 1997, pages 11-14).

1. Missing comma after an introductory element
Many sentences begin with one or more introductory elements—clauses, phrases, or single words that lead into the main body of the sentence. To show where an introductory element ends and the main part of the sentence begins (thus helping your readers move more easily through the sentence), insert a comma after the introductory element. If the sentence includes more than one introductory element, use a comma after each one.

Incorrect: Moreover because the sociological imagination sees human beings from many perspectives sociologists tend to have a particularly insightful view of people.

Correct: Moreover, because the sociological imagination sees human beings from many perspectives, sociologists tend to have a particularly insightful view of people.

2. Vague pronoun reference
Readers should be able to easily identify a pronoun’s antecedent (that is, the specific word or phrase to which the pronoun refers). If the antecedent is unclear (either because there is more than one possible pronoun reference or because the word to which the pronoun refers is implied but not actually stated in the text), you need to make the reference more explicit.

Incorrect: A sociological idea leads to research; this supports or refutes it.

Correct: A sociological idea leads to research; the research findings support or refute the idea.

3. Missing comma in a compound sentence
When two independent clauses (clauses that can stand alone as separate sentences) are joined by a coordinating conjunction such as and, but, so, yet, nor, or for, precede the conjunction with a comma to signal a pause between the two parts of the sentence. The pause gives pace to the sentence and helps prevent sentence misreadings.

Incorrect: The meaning of deviance varies among social systems but deviance as a concept exists in all cultures.

Correct: The meaning of deviance varies among social systems, but deviance as a concept exists in all cultures.

Note: Be sure to distinguish between compound sentences, as defined above, and sentences that have two or more predicate phrases but only one subject. Sentences with a compound predicate do not take a comma between the two parts of the predicate. For example:

Incorrect: Deviance has cultural variations in meaning, but exists as a concept in all cultures.

Correct: Deviance has cultural variations in meaning but exists as a concept in all cultures.

4. Wrong word
Most instances of this error arise from confusion or carelessness regarding homonyms or other words that either sound similar or have similar meanings. Wrong-word errors may also result from overly casual use of a thesaurus.( Be sure to consult a dictionary if you’re not sure of the exact meaning of a word you find in a thesaurus.)

Incorrect: In there inquiries into human behavior, sociologists and anthropologists focus on distinctively different issues.

Correct: In their inquiries into human behavior, sociologists and anthropologists focus on distinctly different issues.

5. Missing comma(s) with a non-restrictive element
Non-restrictive elements are words, phrases, and clauses that provide relevant information in a sentence but are not essential to the sentence’s basic meaning. Non-restrictive elements in a sentence should be set off (on both sides) with commas. In the following example, the non-restrictive element is underlined.

Incorrect: Capitalism which places great importance on ownership of private property encourages relationships that treat people as commodities.

Correct: Capitalism, which places great importance on ownership of private property, encourages relationships that treat people as commodities.

6. Wrong or missing verb ending (-s or –es, -d or –ed)
In spoken English, we sometimes either omit verb endings altogether or pronounce them inaudibly, but standard written English requires their use even when other information in the sentence implies these endings. Make sure that subject and verb agree (plural or singular) and that you are using the correct verb tense. (See also #10.)

Incorrect: The field of sociology attach greatest importance to the workings of human social systems; that of psychology is focus on human behavior at an individual level.

Correct: The field of sociology attaches greatest importance to the workings of human social systems; that of psychology is focused on human behavior at an individual level.

7. Wrong or missing prepositions
A sentence’s meaning may change depending on the preposition you use in conjunction with a verb or as part of a prepositional phrase. For example, the act of comparing something to something else involves looking for similarities among the two items; the act of comparing something with something else means registering both similarities and differences between the items. The acts of meeting at or in an intersection have different implications, as do the acts of talking around, about, or through an issue.

Incorrect: The term structural mobility refers to job mobility that results in changes of the distribution of occupations within a society.

Correct: The term structural mobility refers to job mobility that results from changes in the distribution of occupations within a society.

8. Comma splice
Inexperienced writers sometimes combine two or more independent clauses (clauses that are capable of standing independently as separate sentences) into a single sentence by inserting a comma between the clauses. This error can be corrected in several ways: (1) by separating the clauses into stand-alone sentences; (2) by replacing the comma with a semicolon; (3) by following the comma with a coordinating conjunction such as and, but, so, yet, nor, or for; or (4) by rewriting the sentence to subordinate or eliminate one of the independent clauses.

Incorrect: Ceremonies and holidays are family traditions, they help keep society together.

Correct: Ceremonies and holidays are family traditions. They help keep society together.
or
Ceremonies and holidays are family traditions; therefore, they help keep society together.
or
Ceremonies and holidays are family traditions, and as such, they help keep society together.
or
As family traditions, ceremonies and holidays help keep society together.

9. Missing or misplaced possessive apostrophe
Possessive nouns (nouns that indicate possession of something else) generally have an apostrophe-s ending if singular (e.g. sociologist’s or Davis’s) or just an apostrophe if plural (i.e., sociologists’ or Davises’). Possessive personal pronouns (e.g. hers, his, ours, theirs, yours, and its), however, do not take apostrophes.

Incorrect: A persons socialization can affect her ability to work collaboratively with others.

Correct: A person’s socialization can affect her ability to work collaboratively with others.

10. Unnecessary shift in tense
Unless you have a clear reason for doing otherwise, use the same tense for all verbs both within and across sentences.

Incorrect: Having studied the results, the sociologists report what they found.

Correct: Having studied the results, the sociologists reported what they found.

11. Unnecessary shift in pronoun
When you use a pronoun reference in a sentence, make sure that you use the same pronoun for all subsequent references in the sentence. The most common example of pronoun shifting is the shift between one and I, you, or we.

Incorrect: One does well when we are given role models.

Correct: One does well when one is given role models.
or
We do well when we are given role models.

12. Sentence fragment
A sentence fragment is an incomplete portion of a sentence that is punctuated as a full sentence. To correct this error, incorporate the fragment into the preceding or subsequent sentence, or rewrite the fragment to include subject and predicate. In some types of writing (for example, in fiction and journalistic writing), authors may incorporate fragments as a stylistic choice. In academic writing, however, the use of fragments is far less common.

Incorrect: The perspective she offered helped us resolve the conflict. Giving us a new vantage point from which to view the issue.

Correct: The perspective she offered helped us resolve the conflict by giving us a new vantage point from which to view the issue.
or
The perspective she offered helped us resolve the conflict. It gave us a new vantage point from which to view the issue.

13. Wrong tense or verb form
The verbs in a sentence must clearly communicate whether the condition or action being reported in the sentence is happening in the past, present, or future, whether the action is definite or conditional, and so on. Be on the alert for irregular verbs (verbs that don’t follow the standard pattern for indicating tense) that have been treated as regular verbs.

Incorrect: Last year, a group of sociologists at this Institute has begun examining the connections between cultural norms and domestic violence in patriarchal societies.

Correct: Last year, a group of sociologists at this Institute began examining the connections between cultural norms and domestic violence in patriarchal societies.

14. Lack of subject–verb agreement
The verb form used in a sentence may vary depending on whether the subject is singular or plural and whether the sentence is written in first-, second-, or third person. When you are looking for subject–verb agreement errors, be mindful that the noun closest to the verb may not be the subject.

Incorrect: Theoretical models enhances our understanding of the dynamics of social systems, and a fuller understanding of system dynamics help us create better models.

Correct: Theoretical models enhance our understanding of the dynamics of social systems, and a fuller understanding of system dynamics helps us create better models.

When the subject consists of two or more nouns connected by and, the subject is generally plural. However, when all parts of the subject refer to the same thing or person, the subject is considered singular (see the second example following).

Correct: Both theoretical models and practical experience enhance our understanding of social systems in important ways.

Correct: This definitive study and experimental model serves as a guide for future research.

When the subject consists of two or more nouns connected by or or nor, verb agreement should be with the part of the subject that is closest to the verb.

Correct: Neither the divorce rate nor the many court cases of domestic abuse adequately reflect gender stratification in America.

15. Missing comma in a series
To avoid potential sentence misreadings, always insert a comma between the last two items in a three-or-more-item list.

Incorrect: The systems, conflict and interactionist models should all be considered.

Correct: The systems, conflict, and interactionist models should all be considered.

16. Lack of agreement between pronoun and antecedent
When you use a pronoun (such as you, him, she, their, it) in place of the noun to which it refers (called the pronoun’s antecedent), make sure the pronoun agrees with its antecedent in both gender and number.

Incorrect: The different models all apply in its own way.

Correct: The different models all apply in their own way.

Note also that the words each, every, one, and (often) either and neither are singular and therefore require singular pronoun references. Also, singular noun antecedents joined by or or nor require a singular pronoun.

Incorrect: Each of the models all apply in their own way.

Correct: Each of the models applies in its own way.

Incorrect: Neither the systems nor the conflict model recommend themselves in this situation.

Correct: Neither the systems nor the conflict model recommends itself in this situation.

Some noun antecedents (for example, “sociologist” or “researcher”) are non-gender-specific; that is, these words refer to both males and females. When you use this type of antecedent in its singular form, your pronoun references to the antecedent must acknowledge both genders. You have several options for establishing pronoun agreement with non-gender-specific nouns: (1) For every pronoun reference, use “him and her, “she and he,” etc. Some writers find this awkward and choose instead to alternate between male and female pronoun references either paragraph by paragraph or section by section. (2) You can change the sentence wording to make the antecedent (and therefore the pronoun) plural. (3) You can simply get rid of the pronoun. All three solutions are illustrated here.

Incorrect: Every degree candidate must display his proficiency as a statistical analyst.

Correct: Every degree candidate must display her or his proficiency as a statistical analyst.
or
All degree candidates must display their proficiency as statistical analysts.
or
Every degree candidate must display proficiency in statistical analysis.

17. Unnecessary comma(s) with a restrictive element
Restrictive elements are words, phrases, and clauses that are essential to the basic meaning of the sentence. Do not set restrictive elements apart from the rest of the sentence with commas. In the following example, the intended message is not that all sociologists focus on urban social phenomena, but rather that those who do should read Simmel’s essay.

Incorrect: Sociologists, who focus on urban social phenomena, should read George Simmel’s essay on “Metropolis and Mental Life” (1902-1903).

Correct: Sociologists who focus on urban social phenomena should read George Simmel’s essay on “Metropolis and Mental Life” (1902-1903).

18. Fused sentence
Fused, or run-on, sentences occur when clauses that could stand alone are joined with no linking words or punctuation. Correct this error in one of four ways: (1) Separate the clauses into two (or more) sentences; (2) insert a semicolon between the clauses; (3) insert a comma followed by a coordinating conjunction (e.g. and, but, so, yet, nor, for) between the clauses; or (4) rewrite the sentence to subordinate or eliminate one of the independent clauses.

Incorrect: Sociologists examine all aspects of human life they study conflict and peace, marriage and family, deviance and “normality,” and so on.

Correct: Sociologists examine all aspects of human life. They study conflict and peace, marriage and family, deviance and “normality,” and so on.
or
Sociologists examine all aspects of human life; they study conflict and peace, marriage and family, deviance and “normality,” and so on.
or
Sociologists examine all aspects of human life, for their studies address conflict and peace, marriage and family, deviance and “normality,” and so on.
or
Sociologists examine all aspects of human life as they study conflict and peace, marriage and family, deviance and “normality,” and so on.

19. Misplaced or dangling modifier
To prevent sentence misreadings, place modifying words and phrases as close as possible to the word or words they modify.

Incorrect: She understood better than ever that people are social creatures after reading the textbook.

Correct: After reading the textbook, she understood better than ever that people are social creatures.

20. Its/It’s confusion
Its indicates possession; it’s is a contracted form of it is or it has.

Incorrect: Its an interesting study, but the researchers’ methodology definitely has it’s flaws.

Correct: It’s an interesting study, but the researchers’ methodology definitely has its flaws.

Many of these sample sentences were adapted from Sociology: A Conceptual Approach by Joel M. Charon (2nd ed., Boston: Allyn and Bacon, 1989). Handout prepared by Karen Ritenour, Oregon State University, 1998, and revised by Tracy Ann Robinson. With thanks to Dr. Mark Edwards, OSU Department of Sociology, for his content review.