1.
--- a major role in future planetary exploration.
2.
Unlike the owl, bats cannot see very well, but they do have---.
3.
Comparatively few clues in the United Slates have competing newspapers today, a major change from 1900 --- more than two newspapers.
4.
Witch hazel extract, --- distilled from the bark and twigs of the witch hazel shrub, has been utilized in medicine.
5.
--- touching in O. Henry's stories is the gallantry with which ordinary people struggle to maintain their dignity.
6.
The face of the Moon is changed by collisions with meteoroids, --- new craters to appear.
7.
Social scientists believe that --- from sounds such as grunts and barks made by early ancestors of human beings.
8.
--- substances include various forms of silica, pumice, and emery.
9.
--- in the upper part of their long thin legs allow deer to run swiftly and jump far.
10.
Geophysicists have collaborated with archaeologists and anthropologists to study the magnetic properties of pottery and fireplaces at sites ----- by early humans.
11.
--- technically proficient; it also explores psychological questions.
12.
Although Canada's Parliament can neither administer ------ enforce laws initiate policy, it does have the power to make laws and vote on the allocation of funds.
13.
Willa Cather considered her novel of life in nineteenth-century Nebraska, My Antonia,---
14.
First designated in 1970, Earth Day has become an annual international event ------concerns about environmental issues such as pollution.
15.
In 1992 Albert Gore, Jr., the son of a former United States senator, became----------Vice President of the United States.
