通过改变迎角,无人机飞行员可以控制飞机的()
A.升力.空速.阻力
B.升力.空速.阻力.重量
C.升力.拉力.阻力
参考答案:A
They are leaving for Hangzhou in ten days-________, next Friday. [ ]
A. in other words
B. in many ways
C. on the whole
D. on the contrary
记忆的内容不能保持或者提取有困难就是遗忘。