couplet

Second line: Dark fragrance, agarwood, autumn fragrance, tuberose.

Explanation: The first couplet mentions four kinds of flowers, and the second couplet pairs four kinds of fragrance. Plum blossom has a dark fragrance, osmanthus has agarwood, chrysanthemum has autumn fragrance, and jasmine can correspond to tuberose, which is more suitable from the perspective of semantics and contrast.

Or the second line: Gladiolus, Chlorophytum, Spring Orchid, Phalaenopsis.

Explanation: The first line contains the names of four kinds of flowers, and the second line also contains the names of four orchid plants, which can also correspond well in terms of part of speech and level. .

Or the second line: sandalwood, nanmu, mahogany, agarwood.

Explanation: The first line is the name of a flower, and the second line is the name of four kinds of trees. The contrast is neat.