Interrogative pronouns

Interrogative pronouns are used in interrogative clauses, which may be either main clauses or dependent clauses (so called indirect questions). Most English interrogative pronouns start with wh-, and are therefore often called wh-words. Consequently, interrogative clauses introduced by wh-words are often referred to as wh-questions.

Many interrogatives can function either as determiners or as full noun phrases, i.e. as pronouns proper, while others can have only the latter function.




What colour is his house?

What did she buy for him?


Which side is better?

Which do you prefer?



Who did you meet today?


Whose car is this?

Whose is this car?



To whom did you send it?


In addition to the core cases of interrogative pronouns in this table, the class of wh-words includes the interrogative adverbs where, when, why, and how, as well as the interrogative subordinators whether and if.

What and which as determiners

Both what and which can be used as determiners in noun phrases with personal or non-personal reference.

The use of which is restricted to questions with a limited number of possible answers, which may be given either explicitly or by the context.

(1) Which alternative would you prefer?

(2) Which car is yours?

(3) Which singer did you vote for?

These questions all assume that the speaker and hearer can identify a limited number of alternatives among which the answer can be found. If no such pre-established set of answers is available, what is used instead.

(4) What alternatives do we have?

(5) What car did Roger Moore drive as “The Saint” on TV?

(6) What singer has sold the most albums in the history of pop?

Often, the nature of the expected answer makes it unlikely that a limited set of answers has been established in the discourse. This is true even if, in reality, there is a limited number of possible answers.

Thus, even if there is a limited number of days in the week (or the year), what is the normal choice in questions about times of the day, week-days, dates, etc., as illustrated below. Similarly, even though a book has a limited number of pages, without a pre-established set of pages under discussion, what is the normal choice of determiner.

(7) What day is the race?

(8) What time is it?

(9) What page did you get to?

Who, what and which as pronouns

As a pronoun, which is restricted in the same way as when it is used as a determiner. Thus, it is used only when the answer is to be found among a given limited set of alternatives. The choice of alternatives can be given in a postmodifying prepositional phrase, typically headed by of. Which can be used both about human and non-human referents and both in the singular and the plural.

(10) Which (of these alternatives) would you prefer?

(11) Which of the candidates would be best suited for the job?

(12) Which do you like the most, Bill or John?

If no set of possible answers has been established, who is used for human referents and what for non-human referents. In this case postmodification by an of-phrase is not possible (please remember that * in front of an example indicates unacceptability), although other postmodifiers occur (typically with the role of amplifying the wh-word).

(13) What are our alternatives?

(14) What are your hobbies?

(15) *What of these alternatives seems better? (limited choice indicated by the of-phrase, hence which is used: Which of these alternatives seems better.)

(16) What the hell/on earth/in the world are you saying?

(17) Who told Mary about the accident?

(18) Who are those people?

(19) *Who of your students will pass the exam? (limited choice indicated by the of-phrase, hence which is used: Which of your students will pass the exam?)

(20) Who the hell/on earth/in the world are you talking about?

A Swedish perspective: vem, vad and vilken/vilket (click to expand/contract)

The Swedish interrogatives vem, vad, and vilken and the corresponding English ones who, what, and which overlap to a large extent, but there are also important differences. Thus, whereas the choice between vem/vad on the one hand and vilken on the other is partly determined by the number of the expected answer, the choice between who/what and which is wholly determined by the availability of a limited choice of expected answers:

(1) Vem är bjuden till Maries fest? (sg)

(2) Vilka är bjudna till Maries fest? (pl)

(3) Who has/have been invited to Marie’s party? (sg or pl)

(4) Vem/Vilken av oss tror du hon väljer?

(5) Vilka av oss tror du hon väljer?

(6) Which (one) of us do you think she will choose?

Moreover, vilken, but not vem or vad, is used as a determiner in Swedish, whereas both what and which can be used as determiners in English.

(7a) Vilken bil vill du ha?

(7b) Which car do you want?

(8a) *Vad bil vill du ha?

(8b) What car do you want?

Again, the use of which in English is restricted to questions with a limited number of possible answers.

Moreover, whereas Swedish has a choice between vem and vilken before an av-postmodifier, English can only use which before an of-phrase.

(9) Vem/Vilken av hennes bröder är läkare?

(10) Which (one) of her brothers is a doctor?

As in the last example, English often uses one where the expected answer picks out one of a given set of alternatives.