one SC

redpot

The Audubon Society and other conservation groups, concerned over what they have perceived to be the serious threatening of the environment as posed by the policies of the government, are preparing for a major political effort.

A. have perceived to be the serious threatening of the environment as
B. perceived as the serious threat to the environment as
C. perceive being the serious threat to the environment
D. are perceiving as the serious threatening of the environment
E. perceive as the serious threat to the environment

tongxun

我选A。原因：1、have perceived 一直都如此；2、to be 人为地认为；3、threatening of the environment 可取，但少见threatening of the environment
B、as 。。。as在此导致意思从逻辑上讲不通。
其他选项主要是时态不正确

zinco

the answer may be E.

tongxun

经zinco提醒，再看一下，觉得A选项可能存在的问题在于：concerned over what they have perceived 导致they接了两种时态。
欢迎大家指正！

khe01

I feel that E may be the correct answer since A is too wordy. Please show the correct answer, Redpot. Thanks.

rong

I think b is right.

tongxun

为什么B正确？能给大家解释一下吗？

sunny

我记得这题的答案是D,首先,environment后面绝对不能有as,因为没有对应的部分要求用as,第二,不能用to来连接,因为posed 修饰threatening,如果用to 变成了修饰environment.第三,用进行时没错,和后面的进行时形成对应.第四,perceive sth as 是固定搭配.

tongxun

sunny:欢迎回来！

primefang

真牛, 精彩sunny