Abstract classes may be difficult to understand as to what. Participants felt uncomfortable because I don't know what is wrong? Not suitable for large groups of participants. The instructor must teach the yakan Chana very effectively.
Teaching the abstract may be something incomprehensible. Students feel uncomfortable I do not know what is right and what is wrong. Not suitable for the study group. Tea and experienced instructors must teach more effectively.
Abstract teaching may be understandable to students feel uncomfortable, because do not know what ถูกอะไร wrong. Not suitable for student groups. Teachers must Chan, skillful teaching efficiently.