javascript help with variables

With some help, I wrote this javascript.

http://pastebin.com/uSSZp0j6

I don't understand how to add more than one variable to a variable, I need for there to be several "keycodes," not just one. Other than that, the script works fine.

>>6,8
Please stop programming! new Array? for in 2012? Come on! This is JavaScript, emphasis mine!!!

var keycodes = { "apples":1, "grapes":1, "oranges":1 }
if (y in keycodes)
    x = "correct"
else
    x = "incorrect"