unwritten

adj.

不成文的；口头的，口传的；没有记录的；白纸一张的

unwritten law[律]习惯法；[律]不成文法

1. This is an unwritten constitution.
   这是一个不成文的法规。
2. He bore the unwritten rule in mind.
   他牢记那条不成文的规矩。
3. The missive remains unwritten and unsent.
   这件公文未写也未发出去。
4. This assignment will examine Britain's peculiar unwritten constitution.
   这篇文章将审查英国的有意思的没记录的宪法。

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