class2.html

<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <p id="demo"></p>
    <p id="demo1"></p>
    <p id="demo2"></p>

    <script>
        class student{
            constructor(name,age){
            this.studentname=name;
            this.age=age;
        }
        showname()
        {
            return "STUDENT NAME IS  "+this.studentname;
        }
        }
        class subject extends student{
            constructor(name,sub){
                super(name);
                this.subject=sub;
            }
            showdetail()
            {
                return this.showname()+" HE/SHE TAKES  "+this.subject;
            }
        }
        let student1=new subject("SHANU","SCIENCE");
        let stu2=new student("SHAYOO","14");
        document.getElementById("demo").innerHTML=student1.showdetail();
        document.getElementById("demo1").innerHTML=stu2.showname();
 //document.getElementById("demo2").innerHTML=stu2.showdelail();
    </script>
</body>
</html>