比较的小问题 高手帮帮我啊

dkswoah

The spraying of pesticides can be carefully planned, but accidents, weather conditions that could not be foreseen, and pilot errors often cause much larger deposits of spray than they hadanticipated.
Aweather conditions that could not be foreseen, and pilot errors often cause much larger deposits of spray than they had
weather conditions that cannot be foreseen, and pilot errors often cause much larger deposits of spray than  
unforeseeable weather conditions, and pilot errors are the cause of much larger deposits of spray than they had
weather conditions that are not foreseeable, and pilot errors often cause much larger deposits of spray than
unforeseeable weather conditions, and pilot errors often cause much larger deposits of spray than they had
OA是B   答案说是than they had 这个they 没有明确的指代   
比较的我还有一些不懂    这题目比较的应该是杀虫剂的喷洒量  比预期的要多吧       什么时候要省略代词  （或者说代词没有意义）有没有什么具体的方法呢   这个我一读 感觉 they就是指代杀虫剂啊。。。语法上有点不懂  求高手指教一下    还有解释在排除BD的时候 说 are not foreseeable的表达也有问题  这点也不懂 谢谢XDJM啦

吃饭睡觉打豆豆

小菜豆感觉两个问题，
1. they 肯定不能只带杀虫剂，否者要使用被动。
2. cannot be foreseen和are not  foreseeable 含以上略有不同，can't强调的是能力，be 强调的是状态。

dkswoah

吃饭睡觉打豆豆 发表于 2014-7-22 13:04
小菜豆感觉两个问题，
1. they 肯定不能只带杀虫剂，否者要使用被动。
2. cannot be foreseen和are not  fo ...