It was worker's meal, cooked over open fire. по следует вставить артикли (a/an/the), если нужно. не уверен в том, что думаю, так что о вашей .

1-a
2-the
вроде бы так

1. They had been preparing the medicine for 45 minutes before everything was ready.
2. Doctor had written out the recipes five minutes before I came.
3. We had been looking for a drugstore for about 20 minutes before we found it.
4. I had been reading the medical encyclopedia for a few minutes before I found the desired information.
5. My son had not been waiting even for fifteen minutes when the doctor came.
6. Doctors had worked on this issue for three years before they went on a world scientific conference.

1. What's the theme of the text?
2. What was the thing professor pointed at?
3. What was the way that creature walked?
4. Where did he see them?
5. What are them?
6. Who else could leave sign like that?
7. What was the place they went to?
8. How many of these creatures were there?
9. What height were babies?
10. What height were adults?
11. What's the colour they were painted in?
12. How do their tale look like?
13. How do they look like?
14. What did the children do?
15. What did the big creatures do?
16. What was their strength?
17. What was the feelings of professor?
18. What will scientists say in England?
19. When did they see them?
20. Where did they see them?