()是新中国成立后建设的第一座大型水库。
参考答案:官厅水库
— Sorry, what did you say just now?
— I asked ______. [ ]
A. when did he leave
B. where you have been
C. whom will you go with
D. how I could get to the station
为什么精馏塔塔体歪斜会影响精馏效率?