Selezionare le righe non in un'altra tabella, query di SQL Server

SELECT SubjectID, DepartmentID, SubjectName, SubjectDescription, SubjectShortCode
FROM BS_Subject 
WHERE NOT EXISTS 
(SELECT SubjectToClassID FROM BS_SubjectToClass WHERE 
BS_Subject.SubjectID = BS_SubjectToClass.SubjectID
AND BS_SubjectToClass.ClassID =2)