Sure! Here are the sentences transformed according to your prompts:

8. She managed to find a job immediately after **graduating**.
9. He was **too** drunk to answer my question.
10. **If** I had studied hard, I would have had good marks.
11. It is hard for beginning students to **avoid** making mistakes in English.
12. I **feel** like I’d rather not spend another day at the beach.

If you need further revisions or help with anything else, feel free to ask!