第一节
听下面5段对话。每段对话后有一个小题，从题中所给的[A]、[B]、[C]三个选项中选出最佳选项，并标在试卷的相应位置。听完每段对话后，你都有10秒钟的时间来回答有关小题和阅读下一小题。每段对话仅读一遍。
How is Robin

A．on
B．in
C．at
D．by

A．give an accurate description of the possible disaster in the future
B．prove that humans will sooner or later be destroyed
C．tell the historical development of the Earth
D．warn of a possible disaster in the future