Thus short measure is not hard to give (4)
I believe the answer is:
soft
'not hard to give' is the definition.
I can't judge whether this definition defines the answer.
'thus short measure' is the wordplay.
I cannot quite understand how this works, but
'thus' could be 'so' (synonyms) and 'so' is located in the answer.
'measure' could be 'ft' (ft is a kind of measure) and 'ft' is located in the answer.
No letters remain.
This may be the basis of the clue (or it may be nonsense).
'is' acts as a link.
Can you help me to learn more?
(Other definitions for soft that I've seen before include "firm? On the contrary" , "piano?" , "Easily yielding to pressure" , "Gentle; non-alcoholic" , "p. (mus.)" .)