1. I couldn’t phone you because I didn’t have your number.

→ I didn’t have your number, so I couldn't phone you.

2. They have lived here for two years.

→ They moved here two years ago. 

3. I haven’t visited my family since 2005. (time)

→ The last time I visited my family was in 2005.

4. I’ve been to this restaurant three times now.

→ This is the third time I've been to this restaurant.

5. Matt is still working on his homework.

→ Mark hasn't finished his homework yet.

6. I think that no city is more beautiful than Paris. (most)

→ I think Paris is the most beautiful city in the world.

7. Very few cities in Vietnam are as rich as Da Nang.

→ Da Nang is one of the richest cities in Vietnam. 

8. You should turn unwanted lights off, or you will waste a lot of electricity.

→ If you don't turn unwanted lights off, you will waste a lot of electricity.

9. Learning about recycling is fun.

→ It's funny to learn about recycling. 

10. Remember to turn the tap off when you are brushing your teeth. (forget)

→ Don't forget to turn the tap off when you are brushing your teeth.

1. I didn’t have your number, so I couldn’t phone you.

2. They moved to here two years ago.

3. The last time I visited my family was in 2005.

4. This is the third time I’ve been to this restaurant.

5. Matt haven't finished his homework yet.

6. I think Paris is the most beautiful city in the world.

7. Da Nang is one of the richest cities in Vietnam.

8. If you turn unwanted lights off, you won't waste a lot of electricity.

9. It's fun to learn about recycling.

10. Don't forget to turn the tap off when you are brushing your teeth.