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 had anticipated.
830. 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 had anticipated. (A) weather conditions that could not be foreseen, and pilot errors often cause much larger deposits of spray than they had (B) weather conditions that cannot be foreseen, and pilot errors often cause much larger deposits of spray than (C) unforeseeable weather conditions, and pilot errors are the cause of much larger deposits of spray than they had (D) weather conditions that are not foreseeable, and pilot errors often cause much larger deposits of spray than (E) unforeseeable weather conditions, and pilot errors often cause much larger deposits of spray than they had
A 和B 的区别? 原句could 可以用 can 替换 ? than 后面为什么不加they had ?
830. 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 had anticipated. (A) weather conditions that could not be foreseen, and pilot errors often cause much larger deposits of spray than they had (B) weather conditions that cannot be foreseen, and pilot errors often cause much larger deposits of spray than
这题 第一个can 说明应该用现在时阿。 所以第二个can 而不是could not. 第三个than 是than is anticipated---用被动时