Ⅰ.1. environment
2. universe
3. group
4. None
5. communicated
Ⅱ.6. impossible
7. to go
8. called
9. discovered
10. hundreds
Ⅲ.
11 | 12 | 13 | 14 | 15 |
C | A | A | A | C |
16 | 17 | 18 | 19 | 20 |
C | B | A | C | B |
Ⅳ. 21. over
22. None of us
23. It is, to
24. We haven't found life on other planets yet.
25. Where have you been?
Ⅴ. 26. with, in
27. has, been
28. go around
29. communicating with
30. groups of