Object.create 时，如果不赋值，则是引用

const person = {
  name:"alice",
  say: function() {
    console.log(`My name is ${this.name}`);
  }
};

person.say()
My name is alice

const bob = Object.create(person)

bob.say()
My name is alice

person.name="iris"

bob.say()
My name is iris

bob.name="bob"
'bob'
bob.say()
My name is bob