They speak loudly.
audible
They avoid negative criticism.
positive
They always say 'please' and 'thank you'.
polite
They know everything about their subject.
knowledgeable
They set high standards.
demanding
They give a lot of praise.
generous
They mark and return students' work quickly.
conscientious
They do not allow talking or playing in class.
strict
They tell lots of jokes.
humorous
They play competitive sport.
physically fit