语法:
12.Scientists believe that by [altering] the genetic composition of plants it is possible to develop specimens that are [resisting] to [disease] and have [increased] food
答案为B。我认为D有问题。既然是要去发展一种东西,那怎么用上了完成时呢?怎么都读不通。
23.Thunder can be [listened] from a [maximum] distance of about ten miles [except] under [unusual] atmospheric conditions.
答案为A。why??这里的maximum做形容词解??
26.Although [he is] employed in the scientific and [technical] fields,the metric [system] is not generally [utilized] in the United States.
答案选A。奇怪怎么改呢?如果employ做花费时间解改成主动语态,那么为什么用过去时呢?而主句却用一般时态??
请指教!谢谢