21.If we go on using energy so wasterfully,___are that our oil wells will be dried up before new energy sources can be found to replace oil.
A.opportunities B. chances C. questions D. problems
22.He soon received promotion,for his superiors realized that he was a man of considerable ____.
A.ability B. adult C. academy D. opportunity
21.答案是B,本题考查句型Chances are that…有可能
22.答案是A,根据promotion暗示此人能力强，故选A。
