Exploring _____space is exciting, yet dangerous.
There is _____need for both robots and humans for space exploration.
A.the; a | B.a; a | C./; a | D./; the |
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Exploring _____space is exciting, yet dangerous.
There is _____need for both robots and humans for space exploration.
A.the; a | B.a; a | C./; a | D./; the |