挑高球又分为()和进攻性挑高球
A.攻击性
B.高弧线
C.防守性
D.综合性
参考答案:C
Since you're _____ danger, why not ask _____ help? [ ]
A. in, for
B. in, to
C. with, for
D. with, to
叶片高度不一,倾角太小会导致叶片泵工作压力过高。