// 举例
var ourArray = ["Stimpson", "J", "cat"];
ourArray.push(["happy", "joy"]); 
// ourArray now equals ["Stimpson", "J", "cat", ["happy", "joy"]]


// Setup
var myArray = [["John", 23], ["cat", 2]];


// Only change code below this line.
myArray.push(["dog", 3]);