dull, spiritless / inactive / stagnant

dullness, spiritlessness / inactivity / stagnation

pupil, educatee, student (especially in junior high schools (中学校) or high schools (高校) in Japan)

tedious / boring; dull

tediousness, monotony / boredom, dreariness

be bored

active, vigorous, spirited, perky, vivacious

(rare) activity, vigor, vivacity

instruction; teaching; school; lesson, class

teach; to instruct; give a lesson