1. I don’t play tennis as well as you do.

=> You play tennis better than I do.

2. I haven’t been to the dentist’s for two years.

=> It’s two years since I last went to the dentist’s.

3. Whenever she went to Paris she bought a new dress.

=> She never went to Paris without buying a new dress.

4. I spent seven years at secondary school and then I went to university.

=> After having spent seven years at secondary school I went to university.

5. It’s not worth living to make her change her mind.

=> There’s no need to make her change her mind.