轴流转桨式水轮机,叶片密封装置的作用是()。
A.防止水压降低;
B.防止渗入压力油;
C.对内防油外漏,对外防水渗入;
D.对内防水渗漏,对外防油渗漏。
参考答案:C
—________ the Greens going to move?
—Maybe Beijing or Shanghai. I'm not sure yet. [ ]
A. What is
B. What are
C. Where is
D. Where are
慢性肾小球肾炎患者宜进高蛋白质、高能量食物。()