单项选择题
Harold Urey and Stanley L. Miller did their experiment in order to（）
A．dissolve some new chemicals B．find out what may have happened on the Earth 4 billion years ago C．simulate bolts of lightning on the ancient Earth D．analyze a liquid
单项选择题 May I speak to your manager Mr. Williams at five o'clockI'm sorry. Mr. Williams（）to a conference long before then.
单项选择题 What does "deposit" (L.2, ParA．4) probably mean（）
单项选择题 The passage tells us that（）
