​
There, Their, or They’re? Common Word Mix-ups
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There, Their, or They’re? Common Word Mix-ups
There​
,​
they’re​
, and ​
their ​
are all homophones of each other. Homophones are words
that are spelled differently, have different meanings, but sound the same when spoken.
It is vital to be clear with your word choice because academic writing is all about
communicating new information accurately and clearly. Use this module to explore:
1. Correct usage of commonly mixed-up homophones
2. Additional lists of word mix-ups
1. There, Their, and They’re
1. “There” is an adverb that suggests location or existence.
2. “Their” is a possessive pronoun.
3. “They’re” is a contraction of “they are.” NOTE: Contractions are generally not
accepted in scholarly publications.
Example 1: There, their, and they’re
There​
is a box for the used syringes.
Three graduate students won an award for ​
their​
excellence in humanitarian
engineering.
Do you remember my colleagues Drs. Vince and Allen? ​
They’re​
from the Education
Department
​
There, Their, or They’re? Common Word Mix-ups
www.sites.psu.edu/pubhub
2. Who’s and Whose
1. “Who’s” is a contraction of “who is”
2. “Whose” is a possessive pronoun.
Example 2: Who’s and whose
Who’s​
going to be at the reception tonight?
Whose​
voice is that beautiful?
3. Affect and Effect
1. “Affect” as a verb usually means to influence or to move emotionally. Affect is
also used as a noun, especially in the social sciences.
2. “Effect” as a noun usually refers to a result or consequence. It is also used as a
verb as in ” to effect change.”
Example 3: Affect and effect
Jocelyn did not let the number of impressive presentations at the conference ​
affect
her confidence.
The intervention had a positive ​
effect​
on the participant’s perception of home
gardening.
4. Affective and Effective
1. “Affective” relates to an emotional arousal or response.
2. “Effective” refers to something that was successful or had an intended
consequence.
​
There, Their, or They’re? Common Word Mix-ups
www.sites.psu.edu/pubhub
3. Both words are adjectives.
Example 4: Affective and effective
The commercials had the ​
affective​
results on consumers that the marketing team
hoped for.
Clooney et al. (2009) measured the ​
effectiveness​
of the virtual reality simulator
according to the participant’s fear levels in three different scenarios.
5. Insure and Ensure
1. “Ensure” means “to make certain.”
2. “Insure” denotes a monetary payment to safeguard instances of loss, accident,
etc. (e.g. “health insurance”).
Example 5: Insure and ensure
The scientist ​
ensured ​
that her research participants would experience no ill side
effects from their participation in her study.
Dr. Smith ​
insured ​
the new million dollar lab equipment he just purchased in case of
accidental damage.
6. Than and Then
1. “Than” links words or phrases that are being compared.
2. “Then” is an adverb (meaning it modifies verbs) that suggests something follows
another. “Then” is also used in “if—then” statements.
​
There, Their, or They’re? Common Word Mix-ups
www.sites.psu.edu/pubhub
Example 6: Than and then
Incorrect: ​
The results indicate that agricultural innovation is even more important for
​
future economic growth ​
then​
expected.
“Then” is used incorrectly because this sentence is making a comparison, meaning
the word should be”than”
Corrected: ​
The results indicate that agricultural innovation is even more important
​
for future economic growth ​
than​
expected.
Incorrect: ​
If you need to file a complaint to customer service, ​
​
than​
please fill out the
customer inquiry card.
This is an “if—then” statement so we should use “then,” not “than”
Corrected: ​
If you need to file a complaint to customer service, ​
​
then​
please fill out
the customer inquiry card.
7. Its and It’s
1. “It’s” is a contraction of “it is.”
2. “Its” indicates possessiveness.
Example 7: Its and it’s
It’s​
gratifying to receive good feedback on a conference presentation.
The dog kept wagging ​
its ​
tail during the lab trials.
8. You’re and Your
1. “You’re” is a contraction of you are.
​
There, Their, or They’re? Common Word Mix-ups
www.sites.psu.edu/pubhub
2. “Your” denotes possession.
Example 8: You’re and your
Dr. Smith says ​
you’re ​
one of the top students in class.
Don’t forget ​
your ​
lab coat and goggles for the chemistry demonstration on Thursday.
9. Complement and Compliment
1. “Compliment” refers to words of praise.
2. “Complement” denotes something that adds to or completes something else.
Example 9: Complement and compliment
The student was grateful for the ​
compliment​
his professor gave him.
The slideshow ​
complemented​
the presenter’s talk well.
10. Principle and Principal
1. “Principal” means something that is primary or first.
2. “Principle” refers to a belief or rule.
Example 10: Principle and principal
The ​
principal ​
investigator for this research serves as a board member for Helping
Hands, and has been a reviewer for the professional journal ​
Investigation Quarterly
for two years.
Emily stuck to her ​
principles​
and completed the entire lab even though her partner
wanted to skip a step.
​
There, Their, or They’re? Common Word Mix-ups
www.sites.psu.edu/pubhub
11. Absorb and Adsorb
1. “Absorb” means that something has been soaked up or someone is completely
engrossed in something.
2. “Adsorb” means that molecules, atoms, or ions have adhered to a surface.
Example 11: Absorb and adsorb
The gas molecule ​
adsorbed​
to the polymer in every lab trial.
The ​
absorption​
rate decreased over time.
12. Stationary and Stationery
1. “Stationary” means at a standstill.
2. “Stationery” is something you write on.
Example 12: Stationary and stationery
He likes to exercise on the ​
stationary ​
bike.
She bought new ​
stationery ​
to write letters to her pen pal.
13. Of and Off
1. “Of” is a preposition that denotes connection between two things.
2. “Off” usually indicates a disconnection in something, or an action to undergo to
change something’s state of being, or a change in course or direction. It can be
an adverb or a preposition. In example 13 it is first used as an adverb, and then
as a preposition.
​
There, Their, or They’re? Common Word Mix-ups
www.sites.psu.edu/pubhub
Example 13: Of and off
Barack Obama is the President ​
of​
the United States of America.
The cabin is just North ​
of ​
the lake.
Turn the heat ​
off​
when you go to sleep.
The directions say to pull ​
off​
at the old oak tree.
Sources and Additional Resources:
1. 21st Century Grammar Handbook ​
by the Princeton Language Institute
2. Strunk and White’s ​
The Elements of Style​
.
3. Extensive List of Homophones and Homonyms