1. Despite not preparing for the test, she still has to do it.

2. a) Although Tom was seriously advised by his teacher, he insisted in disturbing the class.

b) In spite of being advised by the teacher, Tom insisted in disturbing the class.

3. a) Although Mary tried several times, she couldn't find a taxi.

b) In spite of trying several times, Mary couldn't find a taxi.

4. Despite feeling tired, he stayed up to keep us company.

5. In spite of not having much time, they came to visit us.

6. a) Although he is too old, he still does his gymnastics every morning.

b) Despite the old age, he still does his gymnastics every morning.

7. In spite of the expensive shirts, people buy them because they are trendy.

8. In spite of having no qualifications, he got the job.

9. a) Although I didn't like the CD you have recommended, I bought it all the same.

b) In spite of  buying the CD you've recommended me all the same, I didn't like it.

10. a) Although I told her all the truth, she didn't believe me.

b) In spite of telling her all the truth, she didn't believe me.

11. a) Although they didn't play well, they won the game.

b) Despite not playing well, they won the game.

12. Despite feeling cold, they didn't turn on the heater.

13. a) Although Bill had a terrible headache, he kept working.

b) In spite of having a terrible headache, he kept working.

14. Despite having all the nescessary books, he doesn't use them to study.

15. a) Although she works very hard, she doesn't deserve a raise.

b) In spite of working hard, she doesn't deserve a raise.