#Program.cs

using System;
using Lesson07.Modals;

namespace Lesson07
{
    class MainClass
    {
        public static void Main(string[] args)
        {
            Console.WriteLine("Hello World!");
            Student std = new Student();
            std.Input();
            std.Display();
        }
    }
}

#Student02.cs

using System;
namespace Lesson07.Modals
{
    public partial class Student
    {
        public string Rollno { get; set; }
        public string Email { get; set; }

        public void Display()
        {
            Console.WriteLine("Hien thi thong tin sinh vien");
        }
    }
}

#Student01.cs

using System;
namespace Lesson07.Modals
{
    public partial class Student
    {
        public string Fullname { get; set; }
        public string Age { get; set; }

        public Student()
        {
        }

        public void Input()
        {
            Console.WriteLine("Nhap du lieu: {0}, {1}, {2}, {3}", Fullname, Age, Rollno, Email);
        }
    }
}