Boost sheep chased by young dog (4,2)
I believe the answer is:
ramp up
'boost' is the definition.
I don't know anything about this answer so I can't tell whether this works.
'sheep chased by young dog' is the wordplay.
'sheep' becomes 'ram' (male sheep).
'chased by' means one lot of letters go next to another (some letters chase after others).
'young dog' becomes 'pup' (short for puppy).
'ram'+'pup'='RAMP UP'
Can you help me to learn more?
(Other definitions for ramp up that I've seen before include "Artificially inflate" , "Add" .)