Features:
(1) Communication:
Official documents and letters play a communication role in consultation and question-and-answer between different subordinate organs, which fully shows the function of parallel language, which is a feature that other official documents do not have.
(2) flexibility:
It is manifested in two aspects: First, the relationship between writing and writing is flexible. Letters are parallel official documents, but they can be written up or down in addition to parallel writing, and there are no strict restrictions on special writing relationships like other languages.
Second, the form is flexible. Except that the main letter of a senior state organ must be written in accordance with the format and writing requirements of the official document, other general letters are flexible and can be handled in accordance with the format and writing requirements of the official document. You can have a home page, or you can have no home page, and you don't have to make a document number or even a title.
(3) uniqueness:
The main content of a letter should be single, and a letter should only write one item.