Answer:
Now, it is important to learn ways people can protect the planet from pollution.
Explanation:
Answers:
1. Can’t be
2. Can’t have won
3. Must have been
4. Must be
5. Couldn’t have been
6. May have been
7. Ought to have left
8. Can’t be
9. Could turn out
10. Must have left
11. Should have won
12. Should be