need. 1 … I take this book for a little while? - I am sorry, but I … return it to the library at once. 2. Alec … practise this sound specially, but the other pupils … not: they…

Certainly! Here is the correctly filled-in version of your exercise with appropriate usage of "must", "may", "can", "should", "ought to", and "will":

1. I take this book for a little while? - I am sorry, but I must return it to the library at once.
2. Alec must practise this sound specially, but the other pupils need not: they all pronounce it properly.
3. They may come any time they like between ten and twelve in the morning, but they need not come if they don't want to.
4. May I go there right now? - Yes, you may.
5. Should we hand in our compositions tomorrow? -- No, you must not, you should hand them in after Sunday.
6. Must John really do this today? -- No, he need not, he can do it tomorrow if he likes.
7. You must not let this cup fall: it will break.
8. May I help you with your coat?
9. You must park your car only in your own space in the back of the building.
10. Peter must return the book to the library. We all want to read it.
11. Why can not you understand it? It is so easy.
12. Shall we do the exercise at once? Yes, you must do it at once.
13. Can you pronounce this sound?
14. May I take your pen? -- Yes, please.
15. We must not carry the bookcase upstairs: it is too heavy.
16. We must not carry the bookcase upstairs ourselves: the workers will come and do it.
17. When will you come to see us? --- I can come only on Sunday.
18. Shall I write a letter to him? -- No, you must not, it is not necessary.
19. You must not** cut anything without a knife.
20. He must not drink alcohol when he drives.
21. Don't worry! I can change a light bulb.
22. By the end of the week I shall have finished writing my book.
23. What can we see on this map?
24. Can you speak Spanish? -- No, unfortunately I cannot.
25. At what time do you come to school?
26. May I come in?
27. You must not** smoke here.
28. May I take your book? - I am afraid not: I need it.
29. He cannot speak English yet.
30. I have very little time: I must go.
31. They need not go to the park today because they are busy.
32. You must read this text: it is easy enough.
33. She still lives in Paris.

Let me know if you'd like any explanations or further assistance!