Question Words
In Russian, there are a number of words used to form questions. You should remember that when you ask a yes/no question it is formed the same was as a statement. (There is no equivalent of words "do", "are"). When you are speaking Russian you should use a rising questioning tone.
Что? - What? (Pronounced "shto")
Как? - How?
Сколько? - How many?
Кто? - Who?
Почему? - Why?
Когда? - When?
Где? - Where? (Used when you are searching for something. "Where is the bank?")
Куда? - (to) Where? (indicates motion towards something. "Where are you going?")
Откуда? - (from) Where? (indicates motion away from something. "Where are you coming from?")
Какой? (m), Какая? (f), Какое? (n) - Which? What sort of?
Чей? (m), Чья? (f), Чьё? (n), Чьи? (pl) - Whose?
Notes: Where gender is shown, the word should agree with the noun it relates to.
The word Какой declines like a stressed adjective, so it must also agree in case.
The words Что? and Кто? have different forms in different cases. Above is nominative. (others shown below)
Advanced Topics:
Different cases of Что? and Кто?
Nominative Case (subject):
Что? - What? (Pronounced "shto")
Кто? - Who?
Accusative Case (object):
Что? - What?
Кого? - Whom?
Dative Case (indirect object):
Чему? - To What?
Кому? - To Whom?
Genitive Case (Possession, negation):
Чего? - What? (Pronounced "chevo")
Кого? - Whom? (Pronounced "kavo")
Instrumental Case (by/with)
Чем? - What?
Кем? - Whom?
Prepositional Case (in/at/about)
Чём - (in/about) What?.
Ком? - (in/about) Whom?
Source: russianlessons.net