TASK DEFINITION: Two analogies on manipulating items in a kitchen is given in the form "A : B. C : ?". The phrase "A : B" relates item A to its appropriate manipulation B. Your task is to replace the question mark (?) with the appropriate manipulation of item C, following the "A : B" relation. Your answer should be a verb which shows a way to manipulate the given object.
PROBLEM: banana : peel. shoe : ?

SOLUTION: untie

PROBLEM: bottle : squeeze. backpack : ?

SOLUTION: unzip

PROBLEM: walnut : shell. shoe : ?

SOLUTION:
untie