Loads of sentences to deal with :)

Hello to everyone reading this Im looking for someone having a perfect command of English. I have 20 sentences in English that need to be checked. I would be extremely
grateful to anyone who could help help me out with these sentences and make a few corrections. Here it is

1. This method has been used in England for many years.
2. In her books there is a lot of valuable information.
3. Rober has much homework to do and so little time.
4. Can you tell me why Joanna neither drinks nor smokes? She used to smoke two packs a day.
5. I've always wondered why such a sensible boy is losing money so often. (is Present Continuous acceptable in this sentence?)
6. More specialists should be interested in those phenomena.
7. You are unlikely to pass that exam if you won't study every day.
8. No sooner had she been promoted than she started to look down on everybody.
9. If it hadn't been for my parents, I wouldn't have achieved so much.
10. We are falling behind with work because the computer hasn't been working for three days now.
11. There is a lot of information in this book. I can't remember it all.
12. Does everybody know that this new method is worth trying?
13. I wish I hadn't spent so much money last week.
14. Few people were interested in single mothers' problems.
15. Adam recommended this place to me, but Julia suggested that I should try something else.
16. Nobody knew about the exam results that were given by the professor yesterday (this one is highly problematic)
17. Never would I think of that this part should have been replaced
18. Several well-known politicians are thought to be involved in the scandal.
19. If you graduate from a good university, you will certainly have better career prospects.
20. Steve has been a doctor for 20 years, which is quite an achievement.

Thank you in advance!