class Student(string First, string Last, int ID, string Street, string City, List<int> Scores)
class Teacher(string First, string Last, int ID, string City)

List<Student> students = new() { … };
List<Teacher> teachers = new() { … };

string peopleInDenver = (
    from student in students
    where student.City == "Denver"
    select student.Last)
    .Concat(
        from teacher in teachers
        where teacher.City == "Denver"
        select teacher.Last);

foreach (var person in peopleInDenver)
    Console.WriteLine(person);

var query1 = from cust in customers
select cust.City; // This select just one member of the source element

var query2 = from cust in customers
select new { Name = cust.Name, City = cust.City }; // This creates an anonymous type that holds
// two properties of the source element.