Our thanks to the Carnegie Mellon Writer’s Style Guide, the primary source for the following, which is used with permission.
adverse/averse
Adverse means unfavorable. Averse means reluctant.
affect/effect
To affect means (1) to influence, change, or produce an effect; (2) to like to do, wear, or use; or (3) to pretend. As a noun, affect is best avoided. (It is occasionally used in psychology to describe an emotion.) Effect is most commonly used as a noun, and it means result. Used as a verb, to effect means to accomplish, complete, cause, make possible, or carry out.
As a general rule, if you’re looking for a noun, you’re probably looking for effect. If you’re using a verb, you’re safest with affect. (A correct use of effect as a verb is: The committee hopes to effect a change in the current policy.)
afterward
not afterwards
all right
not alright
allude/refer
To allude to means to speak of indirectly, without mentioning specifically. To refer to means to speak of directly.
allusion/illusion
An allusion is an indirect reference. An illusion is a false impression or image.
around/about
Around should refer to a physical proximity or surrounding: I’ll look for you around the front of the building. About indicates an approximation: Let’s have lunch about 11:30 a.m.
author
best as a noun, not a verb
beside/besides
Use beside to mean (1) at the side of (sit beside me); (2) to compare with (beside other studies); or (3) apart from (that’s beside the point).
Use besides to mean (1) furthermore (Besides, I said so.); (2) in addition to (and elm and maple trees besides); or (3) otherwise (There’s no one here besides Bill and me.).
between
Between takes an objective pronoun—me, her, him. “Between you and me” is correct; “Between you and I” is not.
biannual/biennial
Biannual means twice a year. Biennial means every two years.
complement/compliment
A complement is something that supplements. A compliment is praise or the expression of courtesy.
compose/comprise/constitute
Compose is to create or put together. Comprise is to contain, to include all, or to embrace. Constitute is to make up, to be the elements of. Never write “is comprised of.”
- Examples:
- The whole comprises the parts.
- The parts constitute the whole.
- The whole is composed of parts.
- The department comprises 12 people.
- Twelve people constitute the department.
- The department is composed of 12 people.
continual/continuous
Continual refers to a steady repetition. Continuous means uninterrupted.
criteria
plural (more than one criterion, which is a quality, a value, or a standard of judgment)
curricula
plural (more than one curriculum, which is a program of academic courses or learning activities)
data
The plural noun usually takes a plural verb.
If used as a collective noun, when the group or quantity is regarded as a singular noun, it takes a singular verb. (The data is sound.)
daylight saving time
not daylight-savings time or daylight-saving time
different from
not different than
disinterested/uninterested
Disinterested means impartial. Uninterested means lacking interest.
eastern standard time
not Eastern standard time
entitled/titled
Entitled means having the right to something. Use titled to introduce the name of a work.
- She is entitled to the inheritance.
- The article is titled “Love and Illusion.”
farther/further
Farther refers to physical distance. Further refers to an extension of time or degree.
fewer/less
In general, use fewer for individual items, less for bulk or quantity.
hang/hung/hanged
Hang means to fasten or suspend, usually from above, with no support from below. Hung is the past tense of this verb and is used to refer to objects. Hanged refers to people and means to kill or commit suicide by suspending from the neck.
- She hangs artwork for the gallery. Last week she hung 48 pieces.
- Police found the prisoner had hanged himself before the trial.
health care
Use as two words without a hyphen in all cases, unless it is treated differently as part of a proper name.
historic/historical
Historic means important in history. Historical refers to any event in the past.
hopefully
Unless you’re describing the way someone spoke, appeared, or acted, do not use this word.
- Right: I hope we can go.
- Wrong: Hopefully, we can go.
- Right: It is hoped the report will address that issue.
- Wrong: Hopefully, the report will address that issue.
- Right: She eyed the interview list hopefully.
imply/infer
Imply means to suggest or indicate indirectly. To infer is to conclude or decide from something known or assumed.
In general, if you imply something, you’re sending out a message. If you infer something, you’re interpreting a message.
in regard to
not in regards to
As regards or regarding may also be used.
insure/ensure
Insure means to establish a contract for insurance of some type. Ensure means to guarantee.
irregardless
Use regardless instead.
-ize
Do not coin verbs with this suffix, and do not use already coined words such as finalize (use end or conclude) or utilize (use the word use).
lay/lie
Lay means to place something or someone down. It must be followed by a direct object. Lie means to rest or recline. Lie is not followed by a direct object. The tenses of these two verbs can be confusing, especially because the simple past form of the verb lie (which is lay) is the same word as the simple present lay. The tenses are as follows: Lay (simple present), laid (simple past), laid (past participle), and laying (present participle). Lie (simple present), lay (simple past), lain (past participle), lying (present participle).
- She usually lays the book on the table, but I don’t know where she laid it this morning.
- When he is sick he likes to lie on the sofa. When he had the flu last week, he lay there for three days straight.
lectern/podium
A speaker stands on a podium and behind a lectern.
let/leave
To let alone means to allow something to remain undisturbed. To leave alone means to depart from or cause to be in solitude.
like/as
Use like to compare nouns and pronouns. Use as to introduce clauses and phrases. Like is the preferred expression (rather than such as) in this kind of phrase: painters like Rubens.
literally/figuratively
Literally means in an exact sense. Figuratively means metaphorically or in a manner of speaking.
- Right: The furnace literally exploded.
- Right: He was so furious he figuratively blew his stack.
- Wrong: He was so furious he literally exploded.
me/myself
Me is the objective case of I. Myself is used reflexively, for emphasis, or in absolute construction.
- Right: It’s between you and me.
- Wrong: You can tell your supervisor or myself.
- Right: I, myself, believe otherwise.
more than/over
Use more than to mean in excess of. Use over when referring to physical placement of an object, an ending, or extent of authority.
- Right: More than 25 professors participated.
- Wrong: The campus has over 50 buildings.
nor
Use this word any time you use neither.
past experience
This is redundant. Use experience alone.
presently/currently
Many writers use these terms as if they were synonymous. The preferred meaning of presently is soon. Presently also can be used to mean for the time being or temporarily. Currently means now. In most cases you can do without using currently. For example, “We are currently revising the plan” works better when simply stated, “We are revising the plan.”
pretense/pretext
Pretense is a false show or unsupported claim to some distinction or accomplishment. Pretext is a false reason or motive put forth to hide the real one—an excuse or a cover-up.
principal/principle
Principal as a noun is a chief person or thing; as an adjective, it means first in importance. Principle is a noun meaning a fundamental truth, doctrine, or law; a guiding rule or code of conduct; or a method of operation.
- John is a principal in the law firm.
- The principal rule in medicine is to do no harm.
- I had difficulty understanding the principles of physics.
rebut/refute
To rebut is to argue to the contrary. To refute is to disprove. However, refute can also mean to deny the truth or accuracy of, as in “refute the allegations.”
regardless
This is a word. Irregardless is nonstandard and should be avoided.
RSVP
Always use RSVP, not rsvp or R.S.V.P.
shall/will
Shall is used for the first-person future tense.
- I shall be indisposed in the days following my surgery.
If will is used for first-person future, it expresses his or her determination or consent. At other times, will is used for the second- and third-person future tense.
- Although I have a cold, I will attend the luncheon tomorrow.
theater/theatre
In references to departments or proper nouns that use the spelling theatre, retain that spelling. In all other cases, use theater.
- Examples:
- Students have many opportunities to go to the theater.
- The Pittsburgh Public Theater and City Theatre both have nice venues.
- Charity Randall Theatre
- Henry Heymann Theatre
- Studio Theatre
toward/towards
Toward is standard U.S. usage; towards is the predominant form in British English and should be avoided.
use/utilize
Use the word use. Utilize is the awkward verb form of the obsolete adjective utile.
-wise
Do not use this suffix to coin words such as weatherwise.