"relaxation has a degree" refers to the characteristics of "artistic expression" in literature. It is most fully expressed in the film art (of course, novels and plays are the same).

Zhang Hechi are two words with opposite meanings, that is, the opening and closing of a bow. This is the original intention. Now

"Zhang" is extended to "intense" and "tense" plot in the movie.

"relaxation" is extended to "soft" and "romantic" scenes in movies.

"moderation" means that the combination of two activities should be focused, primary and secondary, and serve the theme.

a movie is composed of these two parts. Such a 12-minute film can be both fascinating and not tiring.