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6. The white dress is not as expensive as the black one.
7. They think reading books is boring. Therefore, they usually watch TV in their free time.
8. Although Nam's mother bought him many story books, he doesn't like to read them.
9. You shouldn't talk with food in your mouth.
10. The Khmer believe they have to float lanterns, or they may not get good luck.
11. You should not tip in any situation in Japan.
12. You should raise your drink and say "Kampai!" before you drink.
13. Lang Lieu was so poor that he couldn't buy any special food. / Lang Lieu was very poor, so he couldn't buy any special food. 
14. The Hung King Temple Festival was a local festival; however, it has become a public holiday in Viet Nam since 2007.
15. Minh really enjoys hanging out with friends.
16. It is very interesting to play beach games.

III/
1. We were having dinner at 7 p.m last night when the telephone rang.
2. Yesterday was a beautiful day, so my friend and I went on a picnic.
3. My mother likes watching folk music and news on VTV1 channel.