Contractions and Possessive Pronouns, By Andrew Doehrman

David Letterman’s Top Ten Ways to Correctly
use Contractions and Possessive Forms:
10. Many people use its when they
should use it’s. People also
confuse their with they’re as well
as your with you’re.
9. If you have any doubt as to which
word to use in one of these pairs,
you should simply replace the
word you currently have with the
full verb form.
8. If it is, they are, or you are fits
smoothly, the contraction is
correct. If you discover that
using the full verb form makes
the sentence awkward, then the
possessive form is correct.
7. It’s not often that a student from
Indiana University discovers a
dinosaur bone while out jogging.
(It’s is the contraction for it is,
and it refers to the student’s act of
finding a dinosaur bone).
6. The admissions office is grateful
to its student, for his discovery
has resulted in a wealth of
publicity for the university. (Its is
the possessive form, and refers to
the antecedent admissions office).
5. When the Smiths went to their
bungalow for summer vacation,
they found the front door ripped
off its hinges. (Their is the
possessive form of they).
4. When a journalist asked Smith
how his family was coping with
the break-in, he said they’re all
still in shock. (They’re is the
contraction for they are, and
refers to the members of the
Smith family).
3. If your best friend is taking drugs
and robbing banks, you might
want to consider terminating this
relationship. (Your is both the
singular and plural possessive of
you).
2. If you’re not careful, you
could get sucked into his or her
dangerous lifestyle. (You’re is the
contraction for you are, and refers
to the person being advised about
his friend).
1. Its not nice to talk with your
mouth full of food. (In this
sentence, the possessive form
would be incorrect. As you will
realize if you substitute the full
verb form “it is,” the correct word
to use is the contraction it’s).