Email programs typically format the body in single-spaced, full block style to encourage consistency. Try to use short block paragraphs because long paragraphs are more difficult to read. Remember to be considerate of your reader’s time. If your email is likely to take more than two pages, it may be more effective as a letter or memo. You can attach a lengthy letter. Use plain text instead of HTML. (Your reader may not be able to detect unusual fonts or colors). Remember that your reader may also be unable to see your stationery. The best format to follow is to keep it simple.
Keep your email message brief and to the point. If you're a student emailing an instructor-state your question or comment as briefly as possible. (Be sure to include your course ID and section number in the subject line, as well as within the email body.)
Important Tips for Writing Effective Emails