INTERROGATIVE PRONOUNS
These are the pronouns used when asking questions.

Quin?:  Who?
Quines?:  Who? (plural)
A quin?:  Whom?
A quines?:  Whom? (plural)
Qu?:  What?  (asking for information, the definition or identification of something)
Cul?: Which (one)?
Cules?: Which (ones)?

Examples:
Quin rompi la vantana?: Who broke the window?
Quines van contigo?:  Who (all) is going with you?
A quin ves en el espejo?: Whom do you see in the mirror?
Qu es esto?:  What is this (thing)?
Qu hace usted?:  What are you doing?
Qu quiere decir 'anda'?:  What does 'anda' mean?
Cul prefieres? El rojo?:   Which one do you prefer? The red one?
Cul es tu nmero de telfono?:  What is your phone number?
Cul es su lugar de nacimiento?:  What is your place of birth?
Cul es su nacionalidad?:  What is her nationaliity?
