坑穴四壁是成阶地的.The walls of the craters are terraced.海岸顶上是后滨阶地.At the top of the shore is a berm.村镇居民多住二级阶地.Residents live in and towns in the secondary stage....
The American and Japanese navies took the lead in the development of naval aviation...美国和日本海军是发展海军航空部队的佼佼者。The Wright brothers pioneered in early aviation.莱特兄弟是早期航空的先驱.The Gossamer Conder, a human - powered airplane, fle...
A small group of youths stayed behind to heckle and shout abuse.一小群小青年没走，在起哄、叫骂。Crowds of youths prevented the fire service from dealing with the blaze.成群结队的小青年阻拦消防部门灭火。Underage youths can obtain alcohol from their older...