21.
A. It used to be covered with rainforests.
B. It might have been hotter than it is today.
C. It used to have more water than Earth.
D. It might have been a cozy habitat for life.
20.
A. It undergoes geological changes like Earth.
B. It is the same as fiction has portrayed.
C. It is a paradise of romance for alien life.
D. It resembles Earth in many aspects.
Questions 19 to 21 are based on the recording you have just heard.19.
A. Scientists observed Venus from a space vehicle.
B. Scientists found Venus had atmosphere.
C. Scientists discovered water on Venus.
D. Scientists tried to send a balloon to Venus.
18.
A. Visual aids are helpful to all types of learners.
B. Scientific concepts are hard to understand without visual aids.
C. Reading plain texts is more effective than viewing pictures.
D. Auditory aids are as important as visual aids.
17.
A. It was misguided.
B. It was defective.
C. It was thought-provoking.
D. It was original in design.
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