如何使用LINQ在列表中的类中添加两个字段？

public class Person
{
    public string Name { get; set; }
    public int Age { get; set; }
}

List<Person> people = new List<Person>
{
    new Person { Name = "John", Age = 25 },
    new Person { Name = "Jane", Age = 30 },
    new Person { Name = "Bob", Age = 40 }
};

var updatedPeople = from person in people
                    select new Person
                    {
                        Name = person.Name,
                        Age = person.Age,
                        IsAdult = person.Age >= 18,
                        FullName = $"{person.Name} ({person.Age})"
                    };

foreach (var person in updatedPeople)
{
    Console.WriteLine($"Name: {person.Name}, Age: {person.Age}, IsAdult: {person.IsAdult}, FullName: {person.FullName}");
}