- Affect, Effect
- Choose, Chose
- Complement, Compliment
- It’s, Its
- Lead, Led
- Where, Were
- Whether, Weather
- To, Too, Two
- Their, There, They’re
- Than, Then
The following list contains the most common words often confused. Spell Check cannot distinguish between words that are spelled correctly but used incorrectly, so you must be able to distinguish between these words yourself. A dictionary (print, online, mobile app) is an important tool to support your word choice and clarity in writing.
1. Affect, Effect
The freezing rain affected road conditions.
The freezing rain had an effect on road conditions.
Effect can also be used as a verb, meaning "to bring about or accomplish."
The administration effected changes in the structure of the hospital.
2. Choose, Chose
The past tense of the verb choose is chose.
Today I choose to wear red; yesterday I chose to wear green.
3. Complement, Compliment
A complement completes or goes together with something else.
The yellow in the curtains complements the couch.
She gave him a compliment. or She complimented him.
4. It's, Its
It's is a contraction and always means "it is" or "it has."
Its is a possessive pronoun, showing that something is possessed by or belongs to it.
The committee gave its report. (The report belongs to it [the committee]).
Learn more about possessive pronouns.
Tip
When you are writing academic papers, you should not use contractions. So you never really need to write it's in university writing.
5. Lead, Led
The past tense of the verb lead (rhymes with bead) is led.
I know how to lead us home because yesterday I led everyone home.
I keep breaking the lead in my pencil.
6. Where, Were
Were is a form of the verb "to be" in the past.
You were happy when you were a child, weren't you?
7. Whether, Weather
I can't decide whether I should stay or go.
Weather refers to local manifestations of the climate.
The weather outside is frightful.
8. To, Too, Two
Most people can remember that the number 2, when written, is two.
To distinguish between the other two, remember that too means "also" or "as well."
It can also mean "more than enough."
There are too many spelling errors in this essay for it to get an A.
Use to for all other meanings.
9. Their, There, They're
They're is a contraction meaning "they are." Avoid contractions in academic writing.
Use there for all other meanings.
10. Than, Then
Than compares two things. Think compAre - thAn.
Morale was lower than ever before.
Then refers to the time when something happens, and is often used to indicate consecutive actions.
I got up late and then had breakfast.
Then also means "it follows that" or "therefore."
If you don't study, then you will not do well on your exams.