【简答题】____________(环境一旦造成破坏), it takes many years for the system to recover.
【单选题】By the time she takes the entrance examination, Louis ______ Spanish for five years.
C.
will have been studying
【单选题】Many people believe that _______ will takes years to develop a car that does not pollute the air.
【简答题】_____________(环境一旦遭到破坏),it takes many years for the system to recover
【判断题】小球传热实验的实验目的: a. 测定不同环境与小铜球之间的对流传热系数,并对所得结果进行比较。 b. 了解非定态导热的特点以及毕奥准数(Bi)的物理意义。 c. 熟悉实验设备及了解流化床和固定床的操作特点。 d .学会用计算机进行数据采集的方法 f .运用作图方法对实验数据进行分析与处理。