What word do you use when you don’t know the word? Interrogative pronouns like what or who replace unknown nouns, especially in questions. Don’t know the person who called you? Ask “Who called?”
Interrogative pronouns can be confusing, especially when compared to other pronouns or other interrogative parts of speech. Below, we explain everything you need to know about how to use interrogative pronouns.
What is an interrogative pronoun?
Interrogative pronouns are a type of pronoun that replaces a noun when it is unknown. They are most common in interrogative sentences (questions) as a way to request the missing information.
The main interrogative pronouns are what, which, who, whom, and whose. Each has a different type of antecedent (the noun a pronoun replaces). For example, who replaces an unknown person, and what replaces an unknown thing. Interrogative pronouns are similar to indefinite pronouns, except that indefinite pronouns usually refer to something that’s already been identified, whereas interrogative pronouns refer to something unknown.
There are also four compound interrogative pronouns: whatever, whichever, whoever, and whomever. Just like reflexive pronouns add the suffix –self or –selves, interrogative pronouns add the suffix –ever. As interrogative pronouns, these compounds add extra emphasis, implying that the unknown noun is truly a mystery. However, these same words also have different functions as indefinite or relative pronouns (explained below).
Interrogative pronoun examples
Main interrogative pronouns examples
- what
- which
- who
- whom
- whose
Compound interrogative pronouns examples
- whatever
- whichever
- whoever
- whomever
How to use interrogative pronouns
The five interrogative pronouns (and their compound versions) each replace a different type of noun. The correct one to use depends on the kind of noun the interrogative pronoun represents and the pronoun case, such as subject and object pronouns. Interrogative pronouns can be singular or plural without changing the word, but they still need to follow subject-verb agreement, so make sure you conjugate the verb correctly.
| Noun it replaces | Pronoun case | Interrogative pronoun examples | |
| what | thing | subject or object | What is this stain? |
| which | one option in a choice | subject or object | Which is your umbrella? |
| who | person | subject | Who is texting you so late? |
| whom | person | object | Whom are you texting so late? |
| whose | person | possessive | The red truck blocking me is whose? |
For example, if the unknown noun is a person and the sentence treats it like a subject, use who.
[An unknown person] sent me flowers.
Who sent me flowers?
If the unknown is a person and the sentence treats it like an object, use whom.
You voted for [an unknown person].
You voted for whom?
Whom did you vote for?
For whom did you vote?
If the unknown noun is a person and possessive, use whose.
Out of all the performances, [an unknown person’s] was your favorite.
Out of all the performances, whose was your favorite?
Be careful because whose can also be used as an interrogative adjective if it’s used with another noun.
Whose performance was your favorite? [interrogative adjective]
If the unknown noun is a thing, use what regardless of whether it’s the subject or object.
This fruit is called [an unknown thing].
This fruit is called what?
What is this fruit called?
The interrogative pronoun which is a little different because it represents an option or a choice. Even if the options are known or mentioned earlier, we use which when we’re not sure of the option being discussed.
They have pink and red phone cases, so which do you want?
However, be careful because which can also be used as a relative pronoun or an interrogative adjective, both with different functions.
Other interrogative parts of speech
You’re probably wondering why we haven’t yet mentioned why, as well as where, when, and how. While these wh– words are still interrogative, they aren’t interrogative pronouns. They’re either a different part of speech or a different type of pronoun known as a relative pronoun.
Interrogative adverbs
The other popular wh– words where, when, and why, as well as how, are interrogative adverbs. While interrogative pronouns represent unknown nouns, interrogative adverbs represent unknown adverbs. In general, adverbs describe verbs and actions (among other things), such as where, when, or why an event happened.
When does the party start?
Where do you want to get lunch?
Interrogative determiners (interrogative adjectives)
Some of the same interrogative pronouns can also be used as adjectives, words that describe nouns. Specifically, these words are a type of adjective called determiners that specify or identify a noun, especially if there are multiple options. In this sense, interrogative pronouns are similar to demonstrative pronouns, which can also be used as determiners.
Interrogative determiners are easy to find because they always come before a noun, just like other adjectives.
Whose motorcycle is that?
What kind of person eats fried chicken for breakfast?
Relative pronouns
Interrogative pronouns are often confused with relative pronouns because they’re mostly the same words: what, which, who, whom, and whose. The difference between interrogative pronouns and relative pronouns is how they’re used.
Relative pronouns have a very specific function related to clauses. Like conjunctions, relative pronouns connect a relative clause to an independent clause. Relative clauses are a type of subordinate clause (dependent clause), which means they can’t exist in a sentence without an independent clause. The relative pronoun simply acts as a connector.
My neighbors who live above me dance for hours.
I always appreciate a quiet evening at home, which is rare.
Who vs. whom
In English, who vs. whom is one of the most confusing pairs of words. People are always getting them mixed up because they’re both interrogative pronouns that represent people. The difference between who and whom is the case of the word they represent (the antecedent). If the interrogative pronoun is replacing a noun used as the subject, who is correct. If it’s replacing a noun used as an object, whom is correct.
Bellingham [subject] passed the ball to Mbappe [object].
Who passed the ball to Mbappe?
Bellingham passed the ball to whom?
Whose vs. who’s
Another commonly confused pair is whose and who’s. This pair is a little easier because they are two completely different words: Whose is the interrogative pronoun discussed above, and who’s is a contraction for either “who is” or “who has.”
Who’s in charge of knowing whose turn it is at the cash register?
Interrogative pronouns FAQs
What is an interrogative pronoun?
Interrogative pronouns are a type of pronoun that replaces an unknown. They are most common in interrogative sentences (questions) as a way to request missing information.
What’s the difference between regular pronouns and interrogative pronouns?
Regular pronouns are any words that replace other nouns, typically to make communication easier so you don’t have to repeat the same proper name over and over again. Interrogative pronouns are a specific type of pronoun that replace unknown nouns, which is why they’re most often used in questions.
How do you use interrogative pronouns?
The five interrogative pronouns each work with a different type of antecedent (the word a pronoun replaces). What replaces a thing, which replaces an option or a choice, who replaces a person in the subject case, whom replaces a person in the object case, and whose replaces a person as a possessive noun.