Interrogative word
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. They are sometimes called wh-words, because in English most of them start with wh- (compare Five Ws). They may be used in both direct questions (Where is he going?) and in indirect questions (I wonder where he is going). 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).
A particular type of interrogative word is the interrogative particle, which serves to convert a statement into a yes–no question, without having any other meaning. Examples include est-ce que in French, ли li in Russian, czy in Polish, কি ki in Bengali, 吗 ma in Chinese, mı/mi in Turkish and か ka in Japanese. (The English word whether has a similar function but only in indirect questions; and Multicultural London English may use "innit", even in the absence of the pronoun "it".) Such particles contrast with other interrogative words, which form what are called wh-questions rather than yes–no questions.
