标题: 请问 Elory 大神~~ OG-12-95 [打印本页] 作者: gege112 时间: 2012-7-3 01:30 标题: 请问 Elory 大神~~ OG-12-95 The peaks of a mountain range（山脉）, acting like rocks in a streambed, produce ripples in the air flowing over them; the resulting flow pattern, with crests and troughs that remain stationary although the air that forms them is moving rapidly, is known as“standing waves.” （该句为正确句子）
（D）stationary crests and troughs although the air that forms them is moving rapidly, are E) stationary crests and troughs although they are formed by rapidly moving air, is