These two words generally refer to the contrast between sad scenery and sad feelings or happy scenery and happy feelings.
There are two main contrasts in poetry.
One is that the music scene expresses sadness in a lyrical way, and the music scene compares the inner sadness. For example, the most ruthless is Taicheng willow or smoke cage.
There are fewer sad scenes in contrast to joy.
The other is to describe the technique of static by moving and static by sound.
For example, everyone is idle with sweet-scented osmanthus, the spring night is quiet and the mountains are empty, the birds are surprised when the moon comes out, and the spring is ringing when the moon comes out.