The date should go in the upper right corner of the page. Skip one line below it and then type out your address, also justified to the right. Then, skip another line and place your recipient’s full address flush with the left hand side of the page. If you are sending your request via email, you can omit the date and address portions and start with your salutation. However, make sure to use an effective and clear subject line. For example, if you are emailing a professor, your subject line might read, "Mike Smith HIST 359 Paper Extension Request." Start my typing “Dear” and then follow with their title and last name. For example, “Dear Mr. Brady” or “Dear Ms. Smith.” Some titles can be more complicated, such as “Dear Professor Montgomery” or “Dear Senator Smith.”  Even if you know them informally, this is an official request so keep the tone and content formal. Do not write “Hi, Jim,” for example. Try to find some specific person that you can address your letter to. Otherwise, it can appear like a form letter. For example, “Dear Senator Smith,” is preferable to, “To Whom It May Concern.” The body of your letter should be somewhere between 1-3 paragraphs. In many cases, you can open with 1-2 lines, explain your request in 2-4 lines, and conclude in 1-2 lines. If you need to expand to a full three paragraphs, simply separate the introduction, body, and conclusion. To open your letter you might state, “I am John Smith a student in your HIST 456 MWF morning class.” This will jog your professor’s memory and save them time looking you up. Don’t disregard the importance of a solid conclusion. Use your final sentences to restate your case (in one line) and to thank them for their time. You might write, “I appreciate your consideration of my request.”  It is best to close with an official “sign off” before your name. Some of the better options are: “Sincerely” “Best” “All the Best” “Best Regards.”  If you need a reply by a certain time, you should include that information at this point as well. You can always pair it...

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Write a summary of the previous text in Vietnamese:
Trình bày phần đầu trang. Viết lời chào đầy đủ và trang trọng. Sử dụng cách trình bày ngắn gọn. Chú ý phần kết. Ghi tên đầy đủ và chữ ký của bạn.