Question

一道SAT语法题，谢谢啦！

In Germany,foresters discovered that trees killed by acid rian had begun to die four years (earlier without any signs of disease shown then.)
请问括号里的为什么错了？

Answer 1

把shown 改成showing 放到without的后面
shown 作为过去分词做定语,就含有被动的意思了, 被表现出疾病的特征,感觉理解起来怪怪的.
而且前面的主语是树,树自己去表现出来比较好点吧.

Answer 2

In Germany,foresters discovered that trees killed by acid rian had begun to die four years (earlier without any signs of disease shown then.)
提示的意思是树已经死了，句子应该改成：
In Germany, foresters discovered that trees killed by acid rain had already begun to die four years ago.

哥当过sat tutor

Answer 3

earlier 改为before; shown多余了应删去。

Answer 4

shown 改为showing