Sách nói: In the School Room

In the first place, teaching is not simply telling. A class may be told a thing twenty times over, and yet not know it. Talking to a class is not necessarily teaching. I have known many teachers who were brimful of information, and were good talkers, and who discoursed to their classes with ready utterance a large part of the time allotted to instruction; yet an examination of their classes showed little advancement in knowledge. (Summary by John S. Hart)