We are asking people to weigh in on what characteristics made the great teachers they have encountered so great. You can simply list qualities or tell a quick anecdote about that particular teacher that illustrates why you hold him or her in such high esteem.
When completing this task, please spend some time considering what made the teacher a great teacher in total. Was she very knowledgeable? Did he have a great classroom environment? Was she tough but fair? Compassionate? Did he or she get your prepared for your exams particularly well or maybe helped you to learn about yourself in ways you didn't anticipate or just have a class that you looked forward to attending?
If you would like to refer to someone as Mrs. S or Mr. G, for example, that is fine.