If I'm talking with strangers, I'll try to guess how old they are so I can behave in the right way with them. Many times I was wrong in guessing people's ages, but if necessary I have to respect the opponents. For example, I called my old classmate when I was little for a year until I found out her age. I was deceived by his looks and personality. She was small and behaved like a teenager. Plus her face was too young to think she was 2 years older than me. So when she knew my reasons, she didn't get angry with me. Also, if an employee wants to express her respect to me, she will call me as a senior. However, I cannot respond to her and communicate with her as if she were younger than me. I have to react the same way she does with me because it's a rule in Vietnamese culture. If I act like she is younger, she will consider me a rude person. Respect people regardless of your age