Not one of the boys read their SAT study guide.
Isolate: subject: one (singular)
pronoun: their (plural)
This sentence doesn’t sound awful to most people, but it’s wrong. The subject
one is singular, but the pronoun their is plural. (Boys is plural, but it’s an object.
You can tell it’s an object because of the “of the ___” construction.)
The correct pronoun would be his.
Correct: Not one of the boys read his SAT study guide.
Example 2:
Each of the girls ate their lunch.
Isolate: subject: Each (singular)
pronoun: their (plural)
Each is singular, but their is plural. Try replacing the of the girls part of the
sentence with one and you should see why the pronoun her sounds better than
their.
Correct: Each of the girls ate her lunch. (Again, think “each one.”)
There are also some pronouns that can go either way. These are some, any,
none, all, and most. They can be either singular or plural, depending on the
subject. You can remember them easily by combining them into one ridiculous
word that sounds like “suminnynunallmost.”
This word will not be on the SAT.
—Samantha
COMMANDMENT 3: THOU SHALT USE SUBJECTIVE AND OBJECTIVE PRONOUNS
CORRECTLY.
You must know when to use the words in the column on the left and when to use
the words in the column on the right:
Subjects ObjectsI me