Model, short of time, gets soft drink (3)
I believe the answer is:
sip
'drink' is the definition.
(sipping is a kind of drinking)
'model short of time gets soft' is the wordplay.
'model short of time' becomes 'si' (I am not sure about this - if you are sure you should believe this answer much more).
'gets' means one lot of letters go next to another.
'soft' becomes 'p' (musical abbreviation for 'piano').
'si'+'p'='SIP'
Can you help me to learn more?
(Other definitions for sip that I've seen before include "Small mouthful of liquid" , "Drink gingerly" , "Thimbleful" , "Drink slowly" , "Take a little of a drink" .)