Category: General English & Academic English
1) cannot / can not
In informal writing and speech, cannot is usually contracted as “can’t” but in academic writing “cannot” is preferred.
INCORRECT: I can not afford to buy that tablet.
CORRECT: I cannot afford to buy that tablet.
2) effect / affect
Effect is mostly used as a noun which means “something produced by a cause.” but the most use of the effect is as a transitive verb meaning “to act upon”. For example, the disease had a fatal effect on the patient. The teacher’s lack of preparedness affected his teaching process.
INCORRECT: Her father’s death extremely effected her.
CORRECT: Her father’s death extremely affected her.
3) every day / everyday
Everyday functions as an adjective which means “daily” but every day is a phrase which combines the adjective every and the noun day. For example, Practicing is an everyday activity. I go to my office every day.
INCORRECT: Elizabeth walks to the theater everyday at eight a.m.
CORRECT: Elizabeth walks to the theater every day at eight a.m.
4) loose/ lose
The (s) in loose has a soft sound while the (s) in lose has the sound of (z). Loose functions as an adjective which means “not tight”. For example: I do not prefer loose clothing for sleeping. On the other hand, lose functions as a verb “drop, be deprived of, forget, miss”. For example, she frequently loses his wallet in the taxi.
INCORRECT: Be careful not to loose your way.
CORRECT: Be careful not to lose your way.
5) principle/ principal
Principle functions as a noun which means “a general truth or rule”. On the other hand, principal as a noun refers to a person—a person in an authority.
INCORRECT: The principle persuaded the students to follow the rules in school.
CORRECT: The principal persuaded the students to follow the rules in school.
6) between you and me / I
Between is a preposition and meis the object form of pronoun I. So when a pronoun follows a preposition, the object form is needed.
INCORRECT: Keep this secret just been you and I.
CORRECT: Keep this secret just been you and me.
7) less / fewer
Less is used with non-count nouns: less water, less soup.
Fewer is used with countable nouns: fewer students, fewer apples.