Sure! Here are the rewritten sentences with the same meanings:

2. Despite not preparing well for the test, he passed it with very high scores.
3. Despite starting late, I was able to catch up with them.
4. Although she begged him for help, he turned down her request.
5. In spite of living in the city for years, she sometimes gets lost.
6. She often offered to help us, despite not having much time.
7. Despite being young, he behaves in a mature and adult manner.
8. He tried very hard; however, he was unsuccessful.
9. Regardless of how much it might cost, he went ahead with his plan.
10. Although he was an experienced driver, he still had an accident.