Skip to Main Content
It looks like you're using Internet Explorer 11 or older. This website works best with modern browsers such as the latest versions of Chrome, Firefox, Safari, and Edge. If you continue with this browser, you may see unexpected results.
Avoid These Common Grammar Mistakes!
Cartoonist Doug Larson once observed: "If the English language made any sense, a catastrophe would be an apostrophe with fur" [The Quotations Page]. Given the rules and the multiple exceptions to every rule that characterizes the English language, there are many sites on the web that discuss how to avoid mistakes in grammar and word usage. Listed below are the most common and, thus, the ones you should focus on locating and removing while proofreading your research paper.
- Affect / effect -- welcome to what I consider to be the most confusing aspect in the English language. "Effect" is most often a noun and generally means “a result.” However, "effect" can be used as a verb that essentially means "to bring about," or "to accomplish." "Affect" is almost always a verb and generally means "to influence." However, affect can be used as a noun when you're talking about the mood that someone appears to have. [Ugh!]
- Apostrophes -- the position of an apostrophe depends upon whether the noun is singular or plural. For singular words, add an "s" to the end, even if the final letter is an "s." For contractions, replace missing letters with an apostrophe; but remember that it is where the letters no longer are, which is not always where the words are joined [e.g., "is not" and "isn't"].
- Capitalization -- a person’s title is capitalized when it precedes the name and is, thus, seen as part of the name [e.g., President Zachary Taylor]; once the title occurs, further references to the person holding the title appear in lowercase [e.g., the president]. For groups or organizations, the name is capitalized when it is the full name [e.g., the Department of Justice]; further references should be written in lowercase [e.g., the department]. Note that, in general, the use of capital letters should be minimized as much as possible.
- Colorless verbs and bland adjectives –- passive voice, use of the to be verb, is a lost opportunity to use a more interesting and accurate verb when you can. Adjectives can also be used very specifically to add to the sentence. Try to avoid generic or bland adjectives and be specific. Use adjectives that add to the meaning of the sentence.
- Comma splices -- a comma splice is the incorrect use of a comma to connect two independent clauses (an independent clause is a phrase that is grammatically and conceptually complete: that is, it can stand on its own as a sentence). To correct the comma splice, you can: replace the comma with a period, forming two sentences; replace the comma with a semicolon; or, join the two clauses with a conjunction such as "and," "because," "but," etc.
- Compared with vs. compared to -- compare to is to point out or imply resemblance between objects regarded as essentially of a different order; compare with is mainly to point out differences between objects regarded as essentially of the same order [e.g., life has been compared to a journey; Congress may be compared with the British Parliament].
- Confusing singular possessive and plural nouns –- singular possessive nouns always take an apostrophe, with few exceptions, and plural nouns never take an apostrophe. Omitting an apostrophe or adding one where it does not belong makes the sentence unclear.
- Coordinating conjunctions -- words, such as but, and, yet, join grammatically similar elements (i.e., two nouns, two verbs, two modifiers, two independent clauses). Be sure that the elements they join are equal in importance and in structure.
- Dangling participle -- a participial phrase at the beginning of a sentence must refer to the grammatical subject of the sentence.
- Dropped commas around clauses–-place commas around words, phrases, or clauses that interrupt a sentence. Do not use commas around restrictive clauses, which provide essential information about the subject of the sentence.
- The Existential "this" -- always include a referent with "this," such as "this theory..." or "this approach to understanding the...." With no referent, "this" can confuse the reader.
- The Existential "it" -- the "existential it" gives no reference for what "it" is. Be specific!
- Its / it's--"its" is the possessive form of "it." "It's" is the contraction of "it is." They are not interchangeable.
- Fewer / Less -- if you can count it, then use the word fewer; if cannot count it, use the word less.
- Interrupting clause –- this clause or phrase interrupts a sentence, such as, "however." Place a comma on either side of the interrupting clause.
- Know your non-restrictive clauses –- this clause or phrase modifies the subject of the sentence but is not essential to understanding the sentence. The word “which” is the relative pronoun usually used to introduce the nonrestrictive clause.
- Know your restrictive clauses –- this clause limits the meaning of the nouns it modifies. The restrictive clause introduces information that is essential to understanding the meaning of the sentence. The word “that” is the relative pronoun normally used to introduce this clause. Without this clause or phrase, the meaning of the sentence changes.
- Literally -- this word means that exactly what you say is true, no metaphors or analogies. Be aware of this if you are using "literally" to describe something.
- Lonely quotes –- quotes cannot stand on their own as a sentence. Integrate them into a sentence.
- Misuse and abuse of semicolons –- semicolons are used to separate two related independent clauses or to separate items in a list that contains commas. Do not abuse semicolons by using them often. They are best used sparingly.
- Overuse of unspecific determinates -- words such as "super" [as in super strong] or "very" [as in very strong], are unspecific determinates. How many/much is "very"? How incredibly awesome is super? If you ask ten people how cold, "very cold" is, you would get ten different answers. Academic writing should be precise, so eliminate as many unspecific determinants as possible.
- Sentence fragments –- these occur when a dependent clause is punctuated as a complete sentence. Dependent clauses must be used together with an independent clause.
- Singular words that sound plural -- when using words like "each," "every," "everybody," "nobody," or "anybody" in a sentence, we're likely thinking about more than one person or thing. But all these words are grammatically singular: they refer to just one person or thing at a time. And unfortunately, if you change the verb to correct the grammar, you create a pedantic phrase like "he or she" or "his or her."
- Split Infinitive -- an infinitive is the form of a verb that begins with "to." Splitting an infinitive means placing another word or words between the "to" and the infinitive verb. This is considered incorrect by purists, but nowadays it is considered a matter of style rather than poor grammar.
- Subject/pronoun disagreement –- there are two types of subject/pronoun disagreement. Shifts in number refer to the shifting between singular and plural in the same sentence. Be consistent. Shifts in person occurs when the person shifts within the sentence from first to second person, from second to third person, etc.
- That vs. which -- that clauses (called restrictive) are essential to the meaning of the sentence; which clauses (called nonrestrictive) merely add additional information. In general, most nonrestrictive clauses in academic writing are incorrect or superfluous. While proofreading, go on a "which" hunt and turn most of them into restrictive clauses.
- Verb Tense Agreement -- do not switch verbs from present to past or from past to present without a good reason.
- Who / whom -- who is used as the subject of the clause it introduces; whom is used as the object of a preposition, as a direct object, or as an indirect object. A key to remembering which word to use is to simply substitute who or whom with a pronoun. If you can substitute he, she, we, or they in the clause, and it still sounds okay, then you know that who is the correct word to use. If, however, him, her, us, or them sounds more appropriate, then whom is the correct choice for the sentence.
Attending to Grammar. Institute for Writing Rhetoric. Dartmouth College; Avoiding Common Grammar Mistakes. Department of English Writing Guide. George Mason University; Grammar. The Writing Lab and The OWL. Purdue University; Grammar and Mechanics. The Reading/Writing Center. Hunter College; Grammar and Punctuation. The Writer’s Handbook. Writing Center. University of Wisconsin, Madison; Taylor, Dena and Margaret Procter. Hit Parade Of Errors In Grammar, Punctuation, And Style. The Lab Report. University College Writing Centre. University of Toronto.
For more comprehensive guides to avoiding grammar and writing mistakes in your paper, consult these sites: