Teaching it doesn't meen for me to be verbal one. It meens to teach people to SEE. In any perception, first is the quality of seeing.   If you study with a teacher who acquired his understanding only by information, that person may tell you a lot of interesting things, but never change anything in your approach to art. But if you are dealing with a teacher who is completely competent, who is actually living the knowledge, the teaching has become part of his whole being. It goes on and on. There is endless richness. This kind of Teacher will give, give and give. You will receive a lot and you feel there's much more to be said.