// 举例
var ourDog = {
"name": "Camper",
"legs": 4,
"tails": 1,
"friends": ["everything!"],
"bark": "bow-wow"
};


delete ourDog.bark;


// Setup
var myDog = {
"name": "Happy Coder",
"legs": 4,
"tails": 1,
"friends": ["Free Code Camp Campers"],
"bark": "woof"
};


// Only change code below this line.
delete myDog.tails;