I know that was related to a business letter constitutes a form of business communication. A letter to the contact between the business sphere, with the aim either to conduct business. Such as the offering of goods or services, place orders and accept orders following up complaints about errors or damage as a business letter is different from private letters, some in the form of language and phrasing. This is mainly a business letter format and language is quite formal or informal. Do not use slang or colloquial, as often shown in a personal letter and hope for the future.