Interrogative wordwikipedia
An interrogative word or question word is a function word used to ask a question, such as what, when, where, who, whom, why, and how.
interrogative pronouninterrogative wordinterrogativeinterrogativesinterrogative pronounswh-word-everquestion wordinterrogative wordsinterrogative particle

Who (pronoun)

whowhomwho/whom/whose
An interrogative word or question word is a function word used to ask a question, such as what, when, where, who, whom, why, and how.
The pronoun who, in English, is an interrogative pronoun and a relative pronoun, used chiefly to refer to humans.

Five Ws

five WsCircumstancesWho? What? Where? Why? and How? questions
They are sometimes called wh-words, because in English most of them start with wh- (compare Five Ws).
According to the principle of the Five Ws, a report can only be considered complete if it answers these questions starting with an interrogative word:

Question

questionwh-questionanswer
An interrogative word or question word is a function word used to ask a question, such as what, when, where, who, whom, why, and how.
These use interrogative words (wh-words) such as when, which, who, how, etc. to specify the information that is desired.

Interrogative

interrogativeinterrogative sentenceinterrogative mood
For more information about the grammatical rules for forming questions in various languages, see Interrogative.
Interrogative sentences can serve as yes–no questions or as wh-questions, the latter being formed using an interrogative word such as who, which, where or how to specify the information required.

Pro-form

pro-formproformCorrelatives
An interrogative pro-form is a pro-form that denotes the (unknown) item in question and may itself fall into any of the above categories.

Pronoun

pronounpronounspronominal
Subtypes include personal pronouns, reflexive and reciprocal pronouns, possessive pronouns, demonstrative pronouns, relative pronouns, interrogative pronouns, and indefinite pronouns.

List of Latin-script digraphs

ngrrnj
They are sometimes called wh-words, because in English most of them start with wh- (compare Five Ws). Ultimately, the English interrogative pronouns (those beginning with wh in addition to the word how), derive from the Proto-Indo-European root k w o- or k w i, the former of which was reflected in Proto-Germanic as χ w a- or kh w a-, due to Grimm's law.
is used Faroese and Icelandic for (often ), generally in wh-words, but also in other words, such as Faroese hvonn.

Determiner

determinerdeterminersdeterminative
That is, a determiner may indicate whether the noun is referring to a definite or indefinite element of a class, to a closer or more distant element, to an element belonging to a specified person or thing, to a particular number or quantity, etc. Common kinds of determiners include definite and indefinite articles (like the English the and a or an), demonstratives (this and that), possessive determiners (my and their), quantifiers (many, few and several), numerals, distributive determiners (each, any), and interrogative determiners (which).

English language

EnglishEnglish-languageen
They are sometimes called wh-words, because in English most of them start with wh- (compare Five Ws).
In most cases, interrogative words (wh-words; e.g. what, who, where, when, why, how) appear in a fronted position.

Proto-Indo-European pronouns

pronounsIndo-European rootP''k w o-'' or ''k w i
Ultimately, the English interrogative pronouns (those beginning with wh in addition to the word how), derive from the Proto-Indo-European root k w o- or k w i, the former of which was reflected in Proto-Germanic as χ w a- or kh w a-, due to Grimm's law.
There was also a pronoun with the stem (adjectival ) used both as an interrogative and an indefinite pronoun.

English relative clauses

relative clausesrelative pronounsnon-finite relative clause
The words used as relative pronouns have other uses in English grammar: that can be a demonstrative or a conjunction, while which, what, who, whom and whose can be interrogatives.

Relative pronoun

relative pronounrelativerelative pronouns
In English and various other languages the same forms are also used as relative pronouns in certain relative clauses (The country where he was born) and certain adverb clauses (I go where he goes).
For example, the English which is also an interrogative word.

Relative clause

relative clauserelativerelative clauses
In English and various other languages the same forms are also used as relative pronouns in certain relative clauses (The country where he was born) and certain adverb clauses (I go where he goes).
However, the relative clause in (7a) looks more like an indirect question, complete with the interrogative complementiser, kung 'if', and a pre-verbally positioned WH-word like saan 'where', as in (7b).

Indefinite pronoun

indefinite pronounindefiniteindefinite pronouns

Grimm's law

Germanic Sound Shiftdiscoveries of the GrimmsFirst Germanic Sound Shift
Ultimately, the English interrogative pronouns (those beginning with wh in addition to the word how), derive from the Proto-Indo-European root k w o- or k w i, the former of which was reflected in Proto-Germanic as χ w a- or kh w a-, due to Grimm's law.
One of the more conspicuous present surface correspondences is the English digraph wh and the corresponding Latin and Romance digraph qu, notably found in interrogative words (wh-words) such as the five Ws.

Mongolian language

MongolianMongolKhalkha-Mongolian
Other word (sub-)classes include interrogative pronouns, conjunctions (which take participles), spatials, and particles, the last being rather numerous.

Locative adverb

locative adverbhencewhence
They are also usually closely related to locative interrogative adverbs; in English, there is (or, at least, once was) a formal relationship between "where/there/here", "whither/thither/hither", and "whence/thence/hence".

What

what
What is an interrogative pronoun and adverb in English.

Udmurt grammar

plural marker
Udmurt interrogative pronouns inflect in all cases.

Inanimate whose

inanimate ''whoseto things as well as persons
The inanimate whose is restricted to the relative pronoun; English speakers do not use whose as a non-personal interrogative possessive: the whose in "Whose car is this?"

Comparison of Portuguese and Spanish

Spanish and PortugueseSpanishits neighbor and relative
Spanish uses an acute accent on interrogative pronouns, while the corresponding relative pronouns (etymologically the same words) are spelled without the accent to mark the difference in prosodic stress.

Wh-movement

wh-movementwh''-frontingwh-fronting
The special interrogatives, whatever the language, are known within linguistics as wh-words because most interrogative words in the English language start with a wh-; for example, who(m), whose, what, which, etc. Wh-words are used to form questions, and can also occur in relative clauses.

English clause syntax

frontingconditional
In interrogative main clauses, unless the subject is or contains the interrogative word, the verb precedes the subject: Are you hungry? Where am I? (but Who did this?, without inversion, since the interrogative who is itself the subject).

Ngaatjatjarra people

Ngaatjatjarra
The ethnonym Ngaatjatjarra, in line with a general practice in their area, combines the interrogative pronoun used by each tribe for "who", "what".