United Kingdom of Great Britain and Northern Ireland (English: United Kingdom of Great Britain and Northern Ireland), referred to as "Britain". The British Isles, which originated in the northwest of continental Europe, are surrounded by the North Sea, the English Channel, the celtic sea, the Irish Sea and the Atlantic Ocean.

Politeness is the external expression of a person's ideological and moral level, cultural accomplishment and communicative ability, and it is the lowest moral standard that human beings abide by in order to maintain normal social life. It is gradually formed in people's long-term life and communication and is fixed by customs and traditions.

Politeness is a subconscious desire to be respected and appreciated by others, so politeness comes into being. Politeness may be the greatest invention in the history of human civilization. It can help people solve many problems. If the word "please" is used frequently, it will be euphemistic and polite to use the word, which is naturally the best way to lower one's status and raise the other's status.

E-mail refers to files processed by delivery. The process of mail delivery is called "postal service", and the institution or system engaged in postal service is called postal service. There are two kinds of mail: domestic mail and international mail.