How is wallaby surprised? (2,3,3)
I believe the answer is:
on the hop
If this is the answer I cannot explain how the clue works.
Can you help me to learn more?
(Other definitions for on the hop that I've seen before include "Unprepared; busy" , "Be caught...to be taken unawares" , "triple-jumpers must concentrate here first" , "Be caught thus to be caught unprepared" , "Be caught . . . . . . . . to be taken unawares - on one foot?" .)