Obvious Grammatical Errors

Learning Objectives

  • Recognize common grammar and mechanical errors

Grammatically, writers tend to make their most obvious errors in the areas below.


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Subject/verb agreement

    • can usually be addressed by identifying each subject and verb in a sentence, ignoring the other words mentally, and making certain subjects/verbs match in number and sound
  • the word “and” linking two subjects makes them plural, as in, “Grammar and mechanics are related.”
  • when subjects are connected by “or” the subject closer to the verb determines the verb’s number, as in, “Either the punctuation marks or the usage is flawed.”
Verb tense

  • must be considered both for consistency and context
  • writers can switch verb tenses within a paragraph if context calls for it, but unnatural shifts in verb tense stand out loudly, as in, “The sample was heated and then cool before storage.”
  • generally the simplest verb tense should be chosen for the circumstances (avoid “has,” “have,” and “had” as helpers except when necessary)
  • the present tense brings the material “closer” to the reader, so use it whenever possible
Runs-ons and fragments

  • can be addressed by identifying subjects and verbs
  • sentence length can sometimes be a clue

Writers often also have trouble with some commonly confused terms.  The chart below briefly describes a few.

affect vs. effect “Affect” is usually a verb meaning “to influence,” while “effect” is usually a noun meaning “outcome” or “result.”
it’s vs. its “It’s” always means “it is,” while “its” always shows possession.
e.g. vs. i.e. The abbreviation “e.g.” is Latin for exempli gratia and means “for example,” while “i.e.” is Latin for id est and means “that is.”
imply vs. infer The word “imply” means “to suggest” or “to indicate,” while “infer” involves a person actively applying deduction.
that vs. which The word “that” is used to define and limit a noun’s meaning, while “which” is used to provide descriptive information not central to the noun’s definition.

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