哪位大神帮忙看哈错误啊，小弟对这块不是很懂啊

namespace person
{
    public class Person
    {
        public string Name;
        public int Age;
        public Person(string name, int age)
        {
            this.Name = name;
            this.Age = age;
        }
        public void  ShowInfo()

        {
              //  Console.RriteLine(name,age);
                Console.WriteLine("Name is:{0}",Name);
                Console.WriteLine("Age is:{1}",Age);
                return ;
            
        }


  
        public class Student:Person
        {
          //  public string Name;
           // public int Age;
            public int Number;
        
            public  Student(string name,int age , int number):base(name, age)
            {
                this.Name = name;
                this.Age = age;
                this.Number = number;
            }
            public  void ShowNum(int number)
            {
            //    Console.ReadLine(number);
                Console.WriteLine("number is:{2}".Number);
            }
        
        }

    }


  class Program
    {
        static void Main(string[] args)
        {
            Person per = new Person("肖惜淼",22);
            Person.ShowInfo();

        }
    }
}