function Father1(name){ 
    this.name = name; 
} 
 
function Father2(age){ 
    this.age = age; 
} 
 
function Son(name, age){ 
    Father1.call(this,name); 
    Father2.call(this,age); 
} 
 
Son.prototype = Object.create(Father1.prototype); 
Object.assign(Son.prototype, Father2.prototype); 
 
Son.prototype.constructor = Son; 
var lilei = new Son("Lilei",23); 
lilei.name; // "Lilei" 
lilei.age; // 23