()是水轮机调节研究的主要任务。
A.电压调节;
B.电流调节;
C.频率调节;
D.功率调节。
参考答案:C
The driver hurt the girl_____ badly_____ she had to see a doctor.
A.so, that
B.either, or
C.too, to
D.neither, nor、
水平