WH-QUESTIONS

WHO- QUIEN- asking what or which person or people (subject)
Who opened the door?

WHAT- QUE- asking for a reason, asking why 
What did you do that for?

 WHEN- CUANDO- asking about time
 When did he leave?

 WHERE-DONDE- asking in or at what place or position 
Where do they live?
 
WHICH- QUE- asking about choice 
Which colour do you want? 

WHOSE-CUYO-asking about ownership 
Whose are these keys?
Whose turn is it?
 

WHY- POR QUE- asking for reason, asking what...for 
Why do you say that? 

HOW- COMO- asking about manner 
How does this work?