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.