There was an unwritten rule in our office that you worked here for two weeks or a very long time.

We will be raucous, empowered and will turn on its head the unwritten rule that says the old should be weak and invisible.

But not every impersonator abides by the unwritten rule of delivering balance and of keeping their own personal politics out of their work.

But he was also following an unwritten rule.

There's an unwritten rule among publishers never to put a picture of a fish dish on the cover of a cook book.