(2)① The first two sentences of the two poems set off the characters by describing the scenery. ("contrast" can also be written as "setting off": or "scenery description paves the way for the appearance of the characters") ② The last two sentences of the white poem use details (or "expression description") to outline the characters. (3) The last two sentences of Zhang Shi use line drawing technique (or "action description") to sketch the characters.