apply.js

var object = {
  levelOne: function(activity, emotion) {
    console.log('we\'re playing', activity, 'and we feel', emotion, 'about it.')
  }
}

object.levelOne('baseball', 'bored');
//>> we're playing baseball and we feel bored about it. 
 
object.levelOne.apply(this, ['baseball', 'bored']);
//>> we're playing baseball and we feel bored about it. 

// blerg. but still kind of accurate? ;)
object.levelOne.call(this, ['baseball', 'bored']);
//>> we're playing ["baseball", "bored"] and we feel undefined about it.