Don't walk into work after your sick day looking perfectly healthy. Play it up like you're still getting over your illness. Blow your nose a few times or cough softly. You don’t have to play it up too much or act a little too much like a martyr for returning to work. Don’t mention your illness and let other people ask how you’re feeling. You should play it down to be even more authentic, saying something like, “I’m not feeling so bad anymore, really,” or, “I just need one more good night’s sleep and I’ll be just fine.”  If you want to look extra authentic, don't get a lot of sleep the night before so that you show up to work looking haggard and exhausted. This bolsters your credibility for the next time you call in sick (and gives you an excuse to stay up late). Act a little more reserved that day. Don’t be extra friendly or chatty with your coworkers, and turn down invitations. Remember that you still need to save your strength. You may think that you’re close with your coworkers and that they would never rat you out, but you should still be careful about announcing that you were pretending to be sick. Your coworkers won’t want to high-five you, and will think you were being irresponsible or just plain annoying. Plus, if just one coworker repeats what you’ve said and it gets back to your boss, then you will not only get in trouble, but you’ll never be able to fake sick again.  Furthermore, getting called out for faking sick will also make your boss more suspicious the next time you’re actually sick. You don’t want to have to defend yourself for the rest of your time at work. Hey, we all need a day off from work once in a while and there’s no judgment. Still, this doesn’t mean you should go bragging about it, or it’ll show that you really don’t take your work seriously. After calling in sick, you should be nice to your boss when you return to work. You don’t have to mention the illness or thank your boss for being so understanding, but you should work on having a good attitude and sending positive vibes your...

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Write a summary of the previous text in Vietnamese:
Hãy diễn đúng theo kịch bản bạn bị ốm khi quay trở lại làm việc. Đừng nói với đồng nghiệp rằng bạn đã giả vờ ốm. Hãy thân thiện với sếp. Hãy làm việc thật hiệu quả.