观察下列图形,选择一个正确的答案,使它们呈现出一定的规律。()
A.A
B.B
C.C
D.D
参考答案:A
Though there are some differences in American and Chinese education, both systems are ________
excellent graduates. [ ]
A. turning out
B. turning away
C. turning off
D. turning around
轴流式压气机动叶的作用不包括()。
A、输送功率
B、提升速度
C、导向
D、部分增压