A metaphor for the deep feelings between people, especially the feelings and love between husband and wife.

Explanation: It is the legendary "two-winged bird" in China. The male has only the left wing, while the female has only the right wing and the right eye. A male and a female can only fly together. The word "sole" is an ancient name for flounder. In the earliest Erya dictionary in China, the word "sole" was explained, saying that it is a kind of fish with "winning without losing", and two fish must be close to each other before they can act. "Love is deep" means that people have deep feelings, especially the feelings and love between husband and wife.

Synonym: Husband and wife love each other, husband and wife fly together for a hundred years, and the piano and instrument are harmonious. We hope to fly in the sky, like two birds, with the same wing; We hope to grow together on the ground, like two branches of a tree.