Interrogative Pronouns
Learn how who, whom, whose, what and which are used to ask about a person, thing or choice that is not yet known.
Who, whom, whose, what, which
An interrogative pronoun asks about something unknown.
An interrogative pronoun is used to ask a question about a person, thing, or choice that the speaker does not yet know. It takes the place of the answer that has not yet been given.
In the sentence Who called this morning?, the word who stands in for the unknown person who made the call.
English has five interrogative pronouns: who, whom, whose, what and which.
Before you begin
Who and whom follow the same subject and object pattern as other pronouns.
Understanding how subject and object pronouns work can make the difference between who and whom much easier to follow.
If you have not yet covered that lesson, reviewing it first may help.
The central idea
An interrogative pronoun stands in for the missing answer.
Compare a statement with the missing information filled in, and a question asking for it.
01
Statement
The information is already known and stated directly.
Maria called this morning.
02
Question
The interrogative pronoun replaces the unknown information.
Who called this morning?
The useful question is: What piece of information is the question asking for?
Who → a person
What → a thing, action or idea
Which → a choice from a limited set
Whose → an owner
Each interrogative pronoun points toward a different type of missing information.
Who and whom
Who and whom ask about a person, and follow the subject and object pattern.
Who asks about the subject
Who finished the report?
Who stands in for the person performing the action, just like a subject pronoun such as he or she.
Whom asks about the object
Whom did you call?
Whom stands in for the person receiving the action, just like an object pronoun such as him or her.
A useful check
Try answering the question with he or him. If he fits, who is correct. If him fits, whom is correct.
Who called? → He called. → who
Whom did you call? → I called him. → whom
Whom is less common in everyday speech
Many speakers use who in both roles in everyday conversation. Whom is still used in careful or formal writing.
Whose
Whose asks about ownership.
Asking who something belongs to
Whose is this jacket?
Whose can stand alone as a pronoun, or come directly before a noun, as in Whose jacket is this?
What and which
What asks openly. Which asks about a limited set of choices.
01
What
Asks about a thing, action or idea with no limited set of options.
What happened at the meeting?
02
Which
Asks the listener to choose from a known, limited set of options.
Which of these two shirts do you prefer?
The useful question is: Is there a specific, limited set to choose from?
If the possible answers are open-ended, what is usually the better choice. If the speaker already has a specific, limited group in mind, which fits better.
Interrogative pronouns and relative pronouns
The same words can serve a different purpose.
Words such as who, whose and which can also connect a describing clause to a noun, rather than asking a question. This related use is called a relative pronoun.
Interrogative: Who left the door open? (asks a question)
Relative: The person who left the door open forgot to lock it. (connects a clause)
This distinction is explored fully in the Relative Pronouns lesson.
A useful decision guide
Ask what kind of missing information the question needs.
01
Is the question about a person?
Use who for the subject, or whom for the object.
02
Is the question about ownership?
Use whose.
03
Is the question open-ended, with no limited set of answers?
Use what.
04
Is the question about choosing from a known, limited set?
Use which.
Common mistakes
Do not confuse subject and object, or open and limited questions.
Using who where the object form is needed in formal writing.
Less formal: Who did you speak to?
More formal: Whom did you speak to?
Both are widely understood, but careful or formal writing generally uses whom for the object.
Confusing whose with who’s.
Not: Who’s jacket is this?
Correct: Whose jacket is this?
Who’s is a contraction of who is or who has, not a possessive form.
Using what when the choices are already limited.
Less precise: What of these two colours do you like?
More precise: Which of these two colours do you like?
Which fits better once a specific, limited set of options has been introduced.
Check your understanding
Which interrogative pronoun fits?
Choose the correct answer for each question.
__________ organised the surprise party? (asking about the subject)
✅ Exactly! Who asks about the person performing the action.
❎ Not quite. Try answering with he or him to check which form fits.
If the answer would be “he organised it,” use who.
__________ did the manager thank at the meeting? (asking about the object)
✅ Exactly! Whom asks about the person receiving the action.
❎ Not quite. Try answering with him to check which form fits.
__________ do you usually eat for breakfast?
✅ Exactly! There is no limited set of breakfast options mentioned, so what fits.
❎ Not quite. No specific, limited set of choices has been mentioned.
We have tea and coffee. __________ would you like?
✅ Exactly! A specific, limited choice between tea and coffee has already been given.
❎ Not quite. A limited set of two options has already been introduced.
Choose the best explanation
Select the sentence that explains the interrogative pronoun correctly.
Why does “Whom did you call?” use whom rather than who?
✅ Exactly! The unknown person receives the action of calling, so the object form is used.
❎ Not quite. Think about who is performing the calling, and who is being called.
Why is “Which of these two paths should we take?” a good use of which?
✅ Exactly! Which fits well once a specific, limited set of choices has been named.
❎ Not quite. Look at how the two paths are already named as a limited set.
Which sentence correctly asks about ownership?
✅ Exactly! Whose is the possessive interrogative pronoun used to ask about ownership.
❎ Not quite. Look for the word that shows possession without an apostrophe.
Try it another way
Complete the question with the correct interrogative pronoun.
Type the pronoun that fits each question.
✅ Exactly! Who asks about the person performing the action.
❎ Not quite. This question asks about the subject of the sentence.
✅ Exactly! Whose asks who the umbrella belongs to.
❎ Not quite. This question asks about ownership.
✅ Exactly! A specific, limited set of three trains has already been mentioned.
❎ Not quite. A limited set of trains has already been introduced.
Edit the sentence
Rewrite each question with the correct interrogative pronoun.
Use the note in brackets to decide which pronoun fits.
Who’s jacket is this? (correct the possessive form)
✅ Exactly! Whose is the correct possessive interrogative pronoun.
❎ Not quite. Replace who’s with the possessive form that has no apostrophe.
Who did the committee choose for the role? (rewrite using the more formal object form)
✅ Exactly! The unknown person is the object of choose, so whom fits the formal form.
❎ Not quite. Use the object interrogative pronoun in place of who.
We have two routes. What one is faster? (correct the pronoun)
✅ Exactly! A limited set of two routes has already been named, so which fits.
❎ Not quite. Replace what with the pronoun used for a limited set of choices.
Quick review
Each pronoun asks for a different kind of missing information.
Interrogative pronouns — who, whom, whose, what, which — ask about a person, thing or choice that is not yet known.
Who asks about the subject; whom asks about the object.
Whose asks about ownership.
What asks an open-ended question; which asks the listener to choose from a specific, limited set.
The same words can also work as relative pronouns, connecting a clause to a noun rather than asking a question.
Remember
Ask what kind of missing information the question needs.
A person, an owner, an open idea, or a choice from a known set: each of these calls for a different interrogative pronoun. Identifying the type of missing information makes the correct choice much clearer.