Letter writing

We had exams on Letter Writing in schools.

I wish to improve on my writing. What critieria are needed for formal letter/ report/ account writing ? Are there any examples on formal words used? How should i start the writing? What about the tone used. How can i sound less offending and informal? How should I end?

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An example of our school paper:

E.g : Your school has recieved a gift of money from a former student was is now famous. The money can be spent in any way and your principal has asked for ideas.

Write a formal letter to your principal with your plan. You must include the following:

- How much money was given.
-How you will spend the money.
-Why you will spend the money in this way.
-How you will help to put the plan into action
-Why you think the former student will be pleased.

You must cover all five points in detail in your letter. You may add details of your own if you wish.

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