Don't go away to do some fishing? (4,3,4)
I believe the answer is:
hold the line
'don't' is the definition.
Both the answer and definition are verbs in their base form.
Maybe there's a link between them I don't understand?
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for hold the line that I've seen before include "don't cave in!" , "Wait for someone on the phone" .)