Tell you how to write a letter

How to write a letter
Generally speaking, letter writing can be classified into three categories: formal, semiformal, and informal. In each of these three tapes of letters, language and tone differ. While slang and unnecessary abbreviations are not allowed in formal or semi-formal letters, depending on the person to whom you are writing.
A formal letter is normally written to a person in an official capacity. It requires two addresses: the address of the writer and the date appear in the top right hand cor ner; the name, the title, and salutation is “Dear sir / Madam” （if the recipient’s name unknown ）or “dear Mr. / Mrs./ Dr.___. ”Examples of formal letters are a letter of application for employment, a letter of trade, a letters of apology, or a letter of application for admission to a college. Some principles for a formal letters are: 1. You should not use slang in your formal writing. 2. You should not use oral English words in your formal writing .3. You should not use contraction in your formal writing. While a formal letter, you must follow this basic pattern:
（1）Tell your reader why you should write this letter.
（2）Clarity your reasons or provide with facts.
（3）What do you expect your react?
Like a formal letter, a semi-formal letter is written in polite language and a humble tone; no slang is allowed. However, unlike a formal letter, a semi-formal one does not require two addresses. Examples of semi-formal letters include a letter to a family friend who is not your friend directly, a letter to teacher concerning your academic work, or a letter to your resident advisor concerning your absence from a floor meeting. You can write “ thank you ”not “thanks”. “nine o’clock” not“9:00”
Slang and abbreviation are allowed in informal letters, because they are substitutes for informal conversation, proving a way of communicating with close relative or friend who are far way. Casual, chatty language and tone are allowed in informal letters, although they should be suited to the recipient .the tone and language you use in a letter to your parents is different from those you use for your brothers or your friends.
Writing an envelop of a letter in English is different form writing one in Chinese. For a Chinese envelop , the outside address（the address of the receiver）must be on the upper –middle side, and the side. But for an English envelop, however, the outside address （the writer’s address） is on the lower-right side, while the return address is on the
upper-left side. If the envelope is from China to English –speaking countries, it is best to write bilingually.。