1. A standard couplet is always composed of two parts that are in opposition to each other. The first part is called the "upper couplet", also known as "chuju", "opponent" and "duigong". ;The latter part is called the "second line", also called the "couple". Two parts come in pairs. Only the upper couplet or only the lower couplet can only be regarded as half a couplet.
2. Horizontal criticism is an organic part of this kind of couplet. It is often a summary of the entire couplet, a finishing touch, or a text that is consistent with the couplet. It is usually four characters, but there are also two. One word, three words, five words or seven words.
3. Couplets are extremely inclusive. They can combine the characteristics of other styles and absorb the expression techniques of other styles, especially long couplets and super-long couplets, which can simply embody the culmination of Chinese stylistic techniques.
Extended information:
Requirements
1. The number of words must be equal and the sentences must be consistent. Unless the position of a certain word is intentionally left vacant to achieve a certain effect, the number of words in the upper and lower couplets must be the same, no more, no less.
2. The levels should be consistent and the tones should be harmonious. The traditional custom is to use the oblique tone at the end of the first line and the level tone at the end of the second line.
3. The parts of speech should be opposite and the positions should be the same, which is called vacuous versus imaginary, real versus real, that is, noun versus noun, verb versus verb, adjective versus adjective, quantifier versus quantifier, adverb versus adverb, and they are relative. The words must be in the same position.
4. The content should be relevant and connected from top to bottom. The meanings of the upper and lower lines must be connected to each other, but they cannot be repeated.