A Guide to Grammar and Punctuation

Last update: 3/3/2023

Written communication is something few people can avoid, so it's helpful to develop strong grammar skills that will enable you to construct text that is both correct and concise. If you consistently write with grammatical errors, you may find that you limit yourself both professionally and personally. Whether you're constructing personal notes and emails or you write professionally, strong writing skills will carry you through any situation. Learn about some of the most common mistakes so you can work to avoid them.

Common Grammar Errors

  • Active and Passive Voice: Writing in active voice involves making the subject of the sentence perform the action. Passive voice happens when the action happens to the object of the sentence; the subject doing the action is de-emphasized or obscured. Writing with active voice makes your writing stronger and more direct.
  • Misplaced Modifiers: Descriptive words and phrases must be positioned next to the word or words they modify. Placing the descriptive words elsewhere in a sentence can create confusion about the noun being modified.
  • Subject-Verb Agreement: Subjects and verbs must agree to maintain correct grammar. If a subject is plural, the verb must also be plural. If a subject is singular, the verb must match it.
  • Parallel Construction: When constructing a sentence with more than one concept, make sure to use the same grammatical style to keep them parallel.
  • Pronouns: Pronouns must agree with nouns and refer to them directly. If a noun is singular, the pronoun must also be singular. Plural nouns require plural pronouns.
  • Me, Myself, and I: Use "me" if someone else will perform an action to or for you. Use "myself" if you are performing an action on yourself. Use "I" if you are referring to yourself in the subject of a sentence.
  • Your and You're: Use "your" to express possession, and use "you're" as a contraction for the words "you are."
  • They're, There, and Their: The word "they're" is a contraction for the words "they are." The word "there" shows a location. Use the word "their" to show possession.
  • Its and It's: The word "its" is possessive. Use the word "it's" as a contraction for the words "it is."
  • Whom and Who: Use the word "whom" if you are referring to the object of a sentence. The word "who" is appropriate when you are referring to the subject of a sentence.
  • Then and Than: "Then" is generally used as an adverb to indicate a point in time. The word "than" is used for comparisons.
  • Could've and Could Of: Use the contraction "could've" to replace the words "could have." The words "could of" are incorrect when used together.
  • Complement and Compliment: The word "complement" indicates something that goes well with something else. The word "compliment" denotes praise or flattery.
  • Different: Use the word "different" with the prepositions "than" or "from" to contrast people or things that are not the same.
  • Affect and Effect: The word "affect" is usually a verb that describes someone's or something's influence. The word "effect" is usually a noun that means a change or result.
  • Fewer and Less: Use the word "fewer" when referring to countable things or people. Use the word "less" when referring to a noun that doesn't have a plural form or something that can't be counted.

Common Punctuation Errors

  • Commas: Use commas to avoid confusion in sentences. Commas separate independent clauses and introductory clauses to make it easier to understand the message. Commas separate lists, quotations, free modifiers, and phrases unless the clause begins with "that."
  • Colons and Semicolons: Use a colon to introduce a list or an item when the list or item follows an independent clause or a complete sentence. A colon is also appropriate between two sentences if the second sentence builds on the first sentence. A semicolon can separate two clauses if the text after the semicolon can stand alone.
  • Apostrophes: Apostrophes indicate possessive nouns as well as contractions. Apostrophes are incorrect for plural nouns.
  • Quotation Marks: Quotation marks are appropriate for quoted text and unfamiliar or slang terms. Introduce quoted text with a comma, and use a capital letter for the first word of a quoted full sentence.
  • Dashes and Hyphens: A short dash is called an en dash, and a longer dash is called an em dash. Use an en dash to replace the words "to" or "through." An em dash is helpful for creating a strong break in sentence structure. A hyphen joins two words together in a compound modifier, such as "one-way" or "well-known."
  • Acronyms: When using acronyms, always spell out the full term in the first instance. Follow the full term with the acronym in parentheses. For all subsequent uses, simply use the acronym.

Common Spelling Errors

The English language follows standard spelling rules. However, some exceptions do occur. When unsure, consult a dictionary. If you are playing a word game such as Scrabble or Words With Friends, check the dictionary of the game in question as variations may occur.

  • If a base word ends with "E," drop it before adding a suffix that starts with a vowel.
  • If a base word ends with a vowel and a "Y," change the "Y" to an "I" before adding a suffix.
  • If a base word ends with a vowel and a "Y," leave the base word unchanged when adding suffixes "-ed" or "-ing."
  • In most cases, follow the letter "Q" with a "U."

Rules You Can Break

  • Beginning Sentences With Conjunctions: Beginning sentences with conjunctions may cause you to create redundant phrases, which can lead to wordiness. However, occasionally starting sentences with conjunctions can help you create a versatile writing style.
  • Ending Sentences With Prepositions: The standard rule has always prohibited ending sentences with prepositions. However, this grammar rule may lead to strange sentence constructions. Thus, it's permissible to use a preposition at the end of a sentence in some cases.
  • Avoiding Sentence Fragments: Sentence fragments are technically incorrect. However, some stylistic writing can include the use of sentence fragments when it enhances the message you are conveying.