The ozone layer (must be protected) because (it) shields the Earth (from) excessive ultra-vilolet (radiations).

admin2008-10-11  30

问题 The ozone layer (must be protected) because (it) shields the Earth (from) excessive ultra-vilolet (radiations).

选项 A、must protected
B、it
C、from
D、radiations

答案D改为radiation

解析 radiation辐射,放射,是不可数名词。
转载请注明原文地址:https://kaotiyun.com/show/yDIO777K
0

最新回复(0)