He specialize in aeronautics. It is a science of ______.
A. aerolith
B. sailing across the ocean
C. flying in airship
D. the flow of air
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Hydrobiplane is a kind of plane which has ______.
A. two wings and flies in space
B. two wings and flies above water
C. four wings and flies above water
D. four wings and flies in space
Mr. Wilson keeps a shop for selling flowers. We call him a _____.
A. flora
B. grocery
C. florist
D. greengrocer
An astronaut is a person who travels through space in a _____.
A. warship
B. airship
C. steamship
D. spaceship
I'm sure they can ____ the attack.
A. withstand
B. withhold
C. withdraw
D. wither
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