Add code to pass 'you should be able to alter the context in which a method runs', 'you should be able to alter multiple objects at once', and 'you should be able to iterate over an object's own properties'
Add code to pass 'Applies the method of another object in the context of a different object (the calling object); arguments can be passed as an Array object'
Add code to pass 'able to change the context in which a function is called'
Add code to pass 'able to return a function from a function'
Add code to pass 'able to use closures'