Errors in grammar and usage detract from your writing and may cause the reader to question your authority as a writer. Use these proofreading tips and edit for the twenty most common errors identified in a study by Lunsford and Connors.
Read your paper aloud; it’s easier to “hear” the mistakes than to see them. Or, try reading your paper backwards, sentence by sentence. That way your mind will focus on the proofreading rather than the content.
Keep a log of the errors you make frequently and spend some time with a handbook or in the Writing Center in order to understand your frequent errors and correct them in your writing.
The following is a list of common grammar errors. Examples that are specific to certain disciplines can be found here.
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 multiple introductory
elements, use a comma after each one.
Incorrect: Collectively the cashew usually ranks as the third or fourth greatest nut of commerce (by mass) worldwide.
Correct: Collectively, the cashew usually ranks as the third or fourth greatest nut of commerce (by mass) worldwide.Incorrect: If Shelly writes her report on Middlemarch, I will want to read it myself.
Correct: If Shelly writes her report on Middlemarch, I will want to read the novel myself.
Missing comma in a compound sentence:
When two independent clauses (clauses that can stand alone as separate sentences)
are joined by a coordinating conjunction (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: Dividends were paid in 2001 but the company reported a net loss in income.
Correct: Dividends were paid in 2001, but the company reported a net loss in income.
Incorrect: In 2001, the company both paid dividends, and reported a net loss in income.
Correct: In 2001, the company both paid dividends and reported a net loss in income.
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 (a phrase modifying
heterosis) is underlined.
Incorrect: The opposite of heterosis or outbreeding is inbreeding.
Correct: The opposite of heterosis, or outbreeding, is inbreeding.
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: Gram, acid-fast and endospore staining are differential staining procedures.
Correct: Gram, acid-fast, and endospore staining are differential staining procedures.
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:
Incorrect: To believe that freedom of expression is universally available is naïve and unrealistic as the old saw goes, "The right to a free press belongs to those who own the press."
Correct: To believe that freedom of expression is universally available is naïve and unrealistic. As the old saw goes, "The right to a free press belongs to those who own the press."
or To believe that freedom of expression is universally available is naïve and unrealistic; as the old saw goes, "The right to a free press belongs to those who own the press."
or To believe that freedom of expression is universally available is naïve and unrealistic, for as the old saw goes, "The right to a free press belongs to those who own the press."
or To believe that freedom of expression is universally available is naïve and unrealistic, as acknowledged in the old saw that "The right to a free press belongs to those who own the press."
Extra Commas: 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).
Fragments: 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 as an independent clause. 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: That brief but eye-opening visit to the research laboratory was a turning point in my career. Leading to my decision to pursue virus research.
Correct: That brief but eye-opening visit to the research laboratory was a turning point in my career, for it led to my decision to pursue virus research.
or That brief but eye-opening visit to the research laboratory was a turning point in my life. The experience led to my decision to pursue virus research.
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: That set of beliefs fly in the face of reason.
Correct: That set of beliefs flies in the face of reason.
Correct: The men and women who belong to that sect still practice traditions that many of us today consider sexist and discriminatory.
Correct: The sect's founder and leader promotes traditions that many of us today consider sexist and discriminatory.
When the subject consists of two or more nouns connected by or or nor, verb agreement should be with the subject noun that is closest to the verb.
Correct: Neither the leader nor his followers adhere to the principal of free speech.
Run-ons: 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:
Incorrect: We learn about life through our surrounding environment these learned lessons are only part of what shapes our future however.
Correct: We learn about life through our surrounding environment. These learned lessons, however, are only part of what shapes our future.
or We learn about life through our surrounding environment; these learned lessons are only part of what shapes our future, however.
or We learn about life through our surrounding environment, but these learned lessons are only part of what shapes our future.
or Although we learn about life through our surrounding environment, these learned lessons are only part of what shapes our future.
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.
Wrong or Missing Verb Ending: 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.
Incorrect: By "instrument," the actor mean her entire physical self--body and voice--that she use in performance.
Correct: By "instrument," the actor means her entire physical self--body and voice--that she uses in performance.
Unnecessary Shift in Verb 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.
Wrong Verb Tense:
A verb must clearly show when a condition or action is, was, or will be
completed.
Incorrect: The stages of fruit development have included one in which ants were attracted to a specific region of the developing nut.
Correct: The stages of fruit development include one in which ants are attracted to a specific region of the developing nut.
Using a 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: Are interest in cashew began in 1985 with the observation that both single and small groups of cashew trees nationalized around the Calicut district of Kerala, India, were visited by forging ants, spiders, and wasps.
Correct: Our interest in cashew began in 1985 with the observation that both single and small groups of cashew trees naturalized around the Calicut district of Kerala, India, were visited by foraging ants, spiders, and wasps.
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: We compared the communities within the biome with one another to identify their common traits.
Correct: We compared the communities within the biome to one another to identify their common traits.
Vague Pronouns: 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: Although what draws people to theatre and playwriting ultimately remains a mystery, several conditions seem to encourage it.
Correct: Although what draws people to theatre and playwriting ultimately remains a mystery, several conditions seem to encourage this attraction.
Incorrect Pronoun Choice: 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: You can use return-on-assets to measure profitability, but one must consider other ratios as well.
Correct: You can use return-on-assets to measure profitability, but you must consider other ratios as well.
Pronoun / Antecedent Agreement: 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: All species within a given ecological community has its own niche.
Correct: All species within a given ecological community have their own niche.
Incorrect: Within a given ecological community, each species has their own niche.
Correct: Within a given ecological community, each species has its own niche.
Incorrect: An ecologist generally spends a portion of his work week in the field.
Correct: An ecologist generally spends a portion of his or her work week in the field.
or Ecologists generally spend a portion of their work week in the field.
or An ecologist generally spends a portion of the work week in the field.
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 (e.g. sociologists' or Davises'). Possessive personal
pronouns ( hers, his, ours, theirs, yours, its), however, do not take apostrophes.
Incorrect: 2 Live Crews artistic world view must be criticized on the basis of a civilly responsible resistance to the bands' rap narrative.
Correct: 2 Live Crew's artistic world view must be criticized on the basis of a civilly responsible resistance to the band's rap narrative.
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.
