0 Something that is unwritten does not exist in a written or printed form. -- 非书面的；口头的；不成文的
an unwritten constitution 不成文宪法
There's an unwritten rule that you don't wear jeans to work. 上班不穿牛仔裤是条不成文的规定。
Is it not a fact that this unwritten prohibition is most loyally observed by all officers serving?
What about the most important, perhaps, to law and order, the criminal law, much of it unwritten and imperfectly administered?
Small firms may manage quite well with an unwritten structure, where the informal links between staff are adequate to allow smooth functioning of the business.
In both written and unwritten traditions, a complex of thoughts and approaches to music are handed down from teacher to student.
There is an (unwritten) assumption in the analysis of determiners that they cannot be discontinuous; thus, if numerals are determiners, so is anything that can precede them.
The validation of such unwritten rules is more linked to the result than to the procedure used to reach it.
Teachers and pupils draw unwritten contracts for practice such as the amount of time spent on task.
We have before us a difficult mixture of convention, unwritten constitution and flexibility in our constitutional arrangements.
