Why?
Reason!
How old?
Age!
How?
Way!
What?
Things!
How often?
Frequency!
How many?
Quantity - countable!
How long?
Duration!
Who?
People!
Whose?
Possession!
Where?
Place!
How much?
Quantity - uncountable!
When?
Time!
Which?
Choice!
How far?
Distance!