Linq выборка

planner.Adding(new Plan() { Day = "Monday", GroupID = 1, AudienceID = 1, SubjectID = 4, Counter = 1 });
            planner.Adding(new Plan() { Day = "Monday", GroupID = 1, AudienceID = 4, SubjectID = 2, Counter = 2 });
            planner.Adding(new Plan() { Day = "Monday", GroupID = 1, AudienceID = 2, SubjectID = 8, Counter = 3 });
            planner.Adding(new Plan() { Day = "Tuesday", GroupID = 1, AudienceID = 2, SubjectID = 8, Counter = 1 });
            planner.Adding(new Plan() { Day = "Tuesday", GroupID = 1, AudienceID = 1, SubjectID = 1, Counter = 2 });
            planner.Adding(new Plan() { Day = "Tuesday", GroupID = 1, AudienceID = 5, SubjectID = 5, Counter = 3 });

//Тут пытаюсь выбрать Counter
 var pair = planner.FindAll()
                .Where(x => x.Day == day && x.GroupID == groupid)
                .Select(x => x.Counter);
 
 
  var plan = from les in lessons
                     from room in roomss
                     where les.Type == room.Type && les.Lesson == room.Lesson
                     select new {Lesson = les.Lesson, Type = les.Type, Teacher = les.Teacher, Number = room.Number };
 
foreach (var v in plan)
            {
                foreach(var p in pair)
                {
                    Console.WriteLine($"{v.Lesson} - {v.Type} - {v.Teacher} - {v.Number} - {p}");
                }
                    
                
            }