helicopter
词根词缀：
helical adj. 螺旋形的
helic 螺旋 + al …的 → 螺旋形的
helicopter n. 直升机
helic 螺旋 + opt 选择 + er 表机器 → 选择螺旋上升的机器 → 直升机
helix n. 螺旋线；螺旋形
helix = helic
数据来源：新东方英语词汇速记大全
相关例句：
Your baggage will be conveyed by helicopter from the airport to your hotel.
你的行李将用直升机由机场运到旅馆。
'This is the police,' came the amplified voice from the helicopter.
“我们是警察，”直升机上传来扩音器中的声音。
There is a helicopter high up in the sky.
天上有一架直升机。
In this paper, the stability and control of a hingeless helicopter in wind shear were investigated.
研究了无铰直升机在风切变场中的稳定性和操纵性。
A helicopter ferried in more soldiers to help in the search.
一架直升机运来更多的士兵协助搜索。
The helicopter is the first in the world to be designed to serve three hitherto very distinct markets.
这款直升机是世界上首批为满足3个迄今为止完全不同的市场而设计的机型。