Use keyboard in class (4)
I believe the answer is:
type
This clue is a double definition.
'use keyboard' is the first definition.
(type with a keyboard)
'class' is the second definition.
(both can mean a variety or kind)
'in' is the link.
(Other definitions for type that I've seen before include "Kind or class as of people" , "Stamp" , "Courier for example" , "Kind - press keys" , "output, printed" .)