Name three characteristics of a well-written letter

Answers can include any three of the following:
Creates a favorable impression by arousing the reader's interest with the first sentence
Appeals to the reader's point of view
Correct in spelling and grammar
Avoids jargon and stilted phrases
Courteous, friendly, and sincere, promoting goodwill
Accurate, clear, concise, and complete
Flows smoothly
Concludes by telling the reader how to respond
Concludes on a positive note