Paragraph 1 ('Dear Professor Hart,')
Greeting
Paragraph 2 ('I'm writing to let you know ...')
Reason for writing, i.e. the problem
Paragraph 3 ('I have medicine ...')
Supporting facts and details
Paragraph 4 ('Until then, ...')
The solution to the problem (including asking for help, if needed)
Paragraph 5 ('Thank you for ...')
Closing phrase
Paragraph 6 ('Regards, Jameela')
Sign off
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