Dr. Virginia Kidd
California State University, Sacramento

Spelling a simple word incorrectly or making a very basic punctuation error is like wearing a dirty shirt to a job interview. No matter what the content of your message, you come across as a very questionable choice for a good grade, a job, scholarship, promotion, management position, or whatever.

Below are 15 common errors and some work mix-ups that frequently occur in student papers.
Violating basic punctuation codes sends a message that you are not a competent person. PROOFREAD TO INCREASE YOUR CREDIBILITY!

1. NEVER, NEVER, NEVER write "would of"! "Of" is NOT a verb. Write "would have."

2. Do NOT use "being" as a verb by itself in a sentence. Never write a sentence beginning "that being" or "one being"!

EX: One being purple.

3. Periods and commas ALWAYS go inside quotation marks in U.S. usage!

Ex: "The end," said John. John said, "The end."

4. An apostrophe is a code. It has only two meanings:

  • It means letters have been left out, as in "don't" (do not).
  • It indicates belonging, as in "author's reasoning," "speaker's point."


5. Use "an" rather than "a" before a word beginning with the sound of a vowel (a, e, i, o, u).

Ex: She had an idea; wrote an agenda; made an important distinction. NOT: a idea, a agenda.

6. A semicolon (;) ends a thought or series. Use a colon (:) or a dash (--) to introduce a series, or let the text introduce it.

7. A semicolon should precede the word "however" when it connects two sentences.

Ex: The detective was sure of his suspect; however, he lacked evidence.

8. Words used to talk about words, rather than their meaning, are underlined, italicized, or put inside quotation marks.

Ex: The speaker repeated the use of "we" and "us."
Or: The speaker repeated the use of we and us.

9. Quoted material is introduced in two ways.

  • Directly quoted material is preceded by a comma. This is followed by quotation marks and a quote beginning with a capital letter. Ex: Brown stated, "The nation needs this bill."

  • Sometimes you quote only a part of a sentence, using your own introduction to the statement. In that case, no comma is required and the quoted matter does not begin with a capital letter. Ex: Brown stated that the nation "needs this bill."
10. An omission within a quoted sentence is shown by three spaced dots. When the omission occurs at the end of a sentence, a fourth dot is included for the period.

11. Italics (in typing, you can underline) indicate that you are referencing a long work such as a book, magazine, newspaper, film or television series. Quote marks indicate that you are referencing short works, such as articles, chapters, speeches, or TV episodes. (In newspaper and magazine style, titles are not italicized.)

Ex: Read "Victims of Good Fortune" in Newsweek.
Ex: "Barney Goes Ballistic" was this week's episode of Barney.

12. Do not use a comma to set off phrases when the information that would be set off is restrictive (essential to the meaning).

WRONG: Widely acclaimed storyteller, Alyce Smith, will lead the workshop.
RIGHT: Widely acclaimed storyteller Alyce Smith will lead the workshop. (The reader needs the name to know who is speaking. It is essential.)

Do use a comma when the information is nonrestrictive (nonessential). The idea is that if you take out the material encircled by commas, you still know what is said, because the information within commas is not essential.

Ex.: Alyce Smith, a widely acclaimed storyteller, will lead the workshop. (The name is essential; the other is descriptive, but not essential.)

Ex: She wrote of Cleo in her first book, Drums of Learning, published in 1990. (She had only one first book, so the information is not essential.)

WRONG: Seattle writer, Larry Karp, will speak at the store April 4th.
RIGHT: Seattle writer Larry Karp will speak at the store April 4th.

WRONG: "The campaign centers around the theme, "not smoking is cool."
RIGHT: "The campaign centers around the theme "not smoking is cool."

13. A comma goes before a name in direct address.

Ex: How are you, Mary? You go, girl.

14. Use "who" when referring to people, not "that."

Ex: People who (not "that") cares about their community will remain informed.

15. When speaking, never say, "ME AND JACKIE went . . . ." Never, never, never! It's like saying "Me went." Say, "JACKIE AND I went, did, have," etc.

"Affect" is generally a verb. Ex: How did the message affect you?

"Effect" is generally a noun. Ex: What effect did the speech have?

It's -- "it is." Ex: It's an effective commercial.

Its -- possessive, shows owning. Ex: Put the bowl in its place. (Remember ours, yours, its, whose--none of them have apostrophes.)

"Are" is a form of the verb to be. Ex: They are learning quickly.

"Our" means belonging to us. Ex: This is our favorite movie.

Who's -- "who has, who is." Ex: Who's going to Crumbs?

Whose -- possessive, shows owning. Ex: Whose idea is this?

They're -- "they are." Ex: They're working hard.

There -- a place. Ex: Put your paper over there. (NOTE: "Here" is in "there.")

Their -- possessive, belonging to them. Ex: Their report is due.

You're -- "you are." Ex: You're going to learn this quickly.

Your -- belonging to you. Ex: Your idea will shock them.

Where -- a place

Were -- past tense of "are."

Too -- "very." Ex: We thought it was too late to change.


Each other--This phrase is two words and is NOT to be written as one. A lot--This phrase is two words and is NOT to be written as one.

Then--a time; Were you in high school then?

Than--comparing; Casey is shorter than Chris.

Site--a place, including a web site
Cite--to refer to a citation.

Punctuation is a code that alerts the reader to information about the words, just as nonverbal communication carries messages about spoken words. When you violate punctuation conventions, you confuse the reader.




This is the end of this sequence.


A list follows.

would of

This writer meant to write "would have" but is ignorant and definitely should not be hired.

"That being" to begin a sentence

What being? What is this bozo talking about?

speaker's reasoning

the reasoning of the speaker

speakers reasoning

all the speakers were reasoning

Joe meant to write "sweetly."

Joe used the wrong word.

Joe meant to write sweetly.

Joe attempted to sound nice.


Page updated: September 2003