using static System.Console;
using System.Collections.Generic;
 
public class Test {
	public static void Main() {
		var pessoas = new List<Pessoa>() {{ new Pessoa() }, { new PessoaFisica { Nome = "Rod" }}};
		foreach (var pessoa in pessoas) WriteLine(pessoa.EuSou());
	}
}
 
public class Pessoa { //não usei abstract para facilitar o exemplo
	protected int id; //campo
    public virtual string EuSou() => "Não sei quem sou!"; //método virtual
}
 
public class PessoaFisica : Pessoa {
	public string Nome { get; set; } //propriedade
    public override string EuSou() => $"Eu sou {Nome}!"; //método virtual sobrescrito
}
 
//https://pt.stackoverflow.com/q/25831/101

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