【简答题】1 What made you decide on a _________ as a teacher? 2 She _____________ that their plan would mean hard work. 3 They ___________ the land to the south of the Murray River ( 墨累河). 4 The helicopter ( 直升...

【填空题】直升机旋翼的浆叶角是指（）与（）的夹角。

【单选题】When the whole area was ______ by the flood, the government sent food there by helicopter (直升机).

【单选题】应用可靠、有效的（）设备加强特殊区段的运行监测；积极推广直升机航巡。

【简答题】直升机地面效应区：

【单选题】1907年11月13日，（）亲自驾驶他自己研制的全尺寸载人直升机，在无外力帮助下，腾空并悬停20分钟，离地高度0.3米，实现了人类首次有动力直升机的垂直升降飞行。

【单选题】On February 4,1974, the Capital Building, the newest building ha Sao Paulo, was destroyed in a big fire. The fire was started on the 11th floor. Soon the whole floor was on fare. There were 25 floors ...

【单选题】共轴反桨直升机错误的是（）

【单选题】When the whole area was______by the flood, the government sent food there by [heli copter] (直升机).

【单选题】以下（）不是直升机的旋桨类型。