Article in English: Even glancing through your email once or twice quickly will eliminate many simple errors that might have sneaked in while writing it. After you've finished composing, proofread your email for spelling and grammar.  Many email services have a free grammar and spelling checker. The quality of these will depend on your email provider. In some cases, these checkers may not be very accurate. Remember to check your subject line, your greeting, and your valediction (closing). It's easy to gloss over these and focus on only the body of your email. If you're writing an important email, or if you really want to be particularly friendly or polite with someone, read your email from start to finish out loud. Does it sound conversational? If so, your email is ready to send. Rewrite sentences or passages that sound clunky. Use your best judgement when evaluating this. This will vary from person to person, depending on your style of speaking. For important communications, like those intended for business, you may want another person to check the reminder before sending it. If you've written a concise email, this generally takes little time and can help catch even the smallest errors.  Check your online messaging service. Send a message to a friend online asking something like, "Hey, could you read over a short email I have to send? It'll only take a minute." Remember to express your gratitude to anyone who reads over your email. They're doing you a favor, after all.

Summary in Vietnamese:
Đọc kỹ lại nội dung email. Đọc email thành tiếng. Nhờ một người khác xem qua email.