C

B

It is by being good listeners that teenagers can have interactive skills with others.

- Switch off lights and electric appliances when you aren't using them.

- Use LED light globes instead of incandescent bulbs.

- Use natural light to light up the room in the morning instead of electricity.

-...

3. Peter is interested in carving eggshells.

4. In spite of being young, he perfoms excellently.

5. It is about five kilometers from my village to the nearest town.

6. There used to be a bus stop in the city.

Hoa is the most intelligent student in the class.

17. Taylor is a cousin of hers.

18. A friend of mine got a virtual reality device as a birthday gift.

19. Many teenagers prefer chatting on the Internet to meeting their friends in person.

20. The first camera phoned appeared in May 1999 in Japan.

The solar energy is the cheapest.

1. B

2. C

3. B

4. D

5. A

1. You will be overweight if you don't be careful with your diet.

2. Because there was a loud noise next to my door last night, I couldn't sleep.

3. He spends his free time looking after the garden.

4. Peter told Mary that they may go sightseeing in Sa Pa next week.

5. It is very interesting to play beach games.

6. My mother cooks better than my sister.