call，apply,bind

var student={
 name:"马云",
 say:function(){
    console.log(this.name);
 }
}
var f=student.say;
f.call(student);//马云
f.apply(student);//马云

function Person(name,age){
        this.name=name;
        this.age=age;
}
Person.prototype.said=function(){
     console.log(this.name);
}
var teacher=new Person();
var soldier={
    name:"库里"
};
teacher.said.apply(soldier);//库里
teacher.said.call(soldier);//库里