The document discusses a lesson on letter writing in an English language class. It defines what a letter is and explains that while electronic communication is now common, letters are still used for formal communication like job applications and official notices.
It then describes the main types of letters, including formal letters, informal letters, business letters, official letters, social letters, and circular letters. It provides examples of each type.
Finally, it provides tips for writing letters, such as identifying the letter type, using proper greetings and closings, getting straight to the point, using polite language, and keeping formal letters concise. It includes an example letter and questions about the letter.