It is not effective and students can not get good knowledge. If teachers have good imagination, teachers can know how to adapt materials for students. Then students can understand what teachers want to say in this class. A good teacher must use imagination to create different and new materials, then students can really receive the knowledge from teachers' lecture and they can learn very quickly. That teachers are aware of students studying situation is the third important thing.
Every student has different studying ability.
Some students can understand what teachers say in this class, but some students can not . If teachers can notice this situation and teach them to use different ways, then students can really understand the lesson. Many teachers just speak the lecture to students and they don't think about the student's feelings. Learning is not difficult. If teachers can use the right method to teach, all students will like learning from teachers'lecture.