1. Words should be equivalent and sentence breaks should be consistent. In addition to deliberately leaving a place for a word to achieve a certain effect, the number of words in the upper and lower couplets must be the same, neither more nor less.
2. Be even and level, and have a harmonious tone. The traditional habit is to "pucker up and fall flat", that is, the end of the last sentence of the first couplet is puckered up and the end of the last sentence of the second couplet is flat.
3. Parts of speech should be relative and in the same position. It is generally called "virtual to virtual, real to real", which means that nouns to nouns, verbs to verbs, adjectives to adjectives, quantifiers to quantifiers, adverbs to adverbs and related words must be in the same position.
4. Be content-related, from top to bottom. The meaning of up and down links must be interrelated, but they cannot be repeated.
Extended data:
The number of words in the upper and lower couplets must be equal and the content should be consistent, that is, the upper and lower couplets can be "linked" (parallel), and two unrelated sentences can not be combined together to form a couplet.
Although antithesis of couplets has something in common with poetry, it is more demanding than poetry. Couplets can be divided into wide pairs and narrow pairs. Wide pairs can only be formed if the contents of the upper and lower couplets are related, while narrow pairs should be written in strict accordance with the standards of Li Weng Dui Yun. However, in practical couplets, wide couplets are often used, while narrow couplets are rarely used, because the requirements for antithesis are too strict, which restricts people's thinking and is suspected of hurting meaning because of the text.
Baidu encyclopedia-couplets