11. Not all national parks have...... tours for children.a. guide
b. guiding
c. guided
d. To guide
12. Hollows of old trees are good......... for nesting animals.
A.place
B. Placing
C. Places
D. To place
13. Native bush may encourage native animals......... back.
A. come
B. Came
C. Comes
D. To come
14. Native bush needs to be gradually....
a. regenerate
b. regenerating
c. regenerated
d. to regenerate
15. We cloud ..... a group of conservation.
a. join
b. joining
c. joined
d. to join
16. We may put......... endangered animals in our neighborhood.
a. much
b. some
c. a little
d. a great deal of
17. We may not......... our rubbish anywhere in a national park.
a. throw
b. throws
c. throwing
d. threw
18. We must not cut down old trees .........they are dangerous.
a. though
b. because
c. but
d. so
19. We must not kill or slaughter......... species. a. endanger
b. endangering
c. endangered
d. to endanger
20. We must .......... some wild animals in a natural forest.
a. put
b. puts
c. putting
d. to put​