1. It's three years since we last visited Ha Noi.
   - We haven't visited Ha Noi for three years.

2. No one is more intelligent than her in our school.
   - She is the most intelligent person in our school.

3. You can't take this book away.
   - This book can't be taken away.

4. Huong is 1.60m tall and Hoa is 1.60m tall, too.
   - Huong is as tall as Hoa.

5. I wrote that letter in half an hour.
   - It took me half an hour to write that letter.

6. She'd rather play golf than play tennis.
   - She prefers playing golf to playing tennis.

7. I had a cat once, but I don't any more.
   - I used to have a cat.