Couplets should be paired. If there is only the first couplet, and the second couplet is not matched, there is a special term called "Pian Yu". Pian Yu, which Hong Kong people are most familiar with, is probably the following:

Shi Bao Bao Shi Bao

This is Cantonese "Pian Yu". The first "Bao" is an edible "steamed stuffed bun" (noun), and the second "Bao" is equivalent to the meaning (verb) of "guarantee" in Mandarin. "Food" and "treasure" are combined into the word "full". It's really hard to think right. According to a letter from He Zhongxian, an old doctor of traditional Chinese medicine in San Francisco,

Similarly, in the early years of the Republic of China, Bao Chao also published a copy of this book, but so far it seems that no one can get its rights. This copy is:

Peanuts, raw flowers, groundnuts;

Groundnut is the scientific name of peanut. Peanuts grow and bloom after planting (peanuts), and the flowers are regenerated upside down, so they are called "groundnuts". "groundnut with flowers" is a reproductive process of peanuts, which goes on and on. That is to say, it can be pronounced as peanuts, flowers, groundnuts, peanuts, .....................................................................................................................................................

Dr. He Zhongxian also has a homemade "Pian Yu", which has been unparalleled for more than 30 years. The first part is:

Geese don't eat grass.

"Goose doesn't eat grass" is the name of medicine, and "grasshopper" is also the name of medicine. It's hard to be right here.

I haven't checked out yet