1. The Vietnamese celebrate several festivals every year.
=> Several festivals are celebrated by The Vietnamese every year.
2. People often hold the Flower Fair on Nguyen Hue Street in Ho Chi Minh City during.
=> The Flower Fair is often held on Nguyen Hue street in Ho Chi Minh City during Tet.
3.Santa claus gives children presents on christmas Eve
=>Children are given presents by Santa claus on Christmas Eve
4.Could you turn off the lights, please
→Would you mind if I turned off the lights?
5.Can i use your mobile phone?
=>Do you mind....using your mobile phone?
6.will you post the letters for me
=>would you mind posting the letter for me?