Some words, or phrases, are reserved. If you try to send a message containing these works or phrases, it will be ignored. If you try to send it as a whisper to another player, you will get the system error message:
Unable to send chat to %t because your message contained reserved words.
Sample words list[]
- you kow
- u kow
- ukow
Reason[]
It's not the phrases that are banned, but the appearance of specific letters.
- kur kow
- you kow
The above are both blocked because of "ukow", which is a reference to a gold selling site which is against the Terms of Use Agreement.
Why someone would need to say these things in English, unless it is a typo for "you know" or "your cow", is unknown.
In Polish language, howewer, it's part of many words: for example "bukowy" (made of beech wood), and it happened more than once to Polish World Of Warcraft players that their whisper message were blocked.