Ozone, a special form of oxygen that screens out harmful

lainemai

Ozone,a special form of oxygen that screens out harmful ultraviolet rays, reacheshigh concentrations twelve miles above Earth, where it has long appearedthat it was immune from human influence; we have now realized, though, thatemissions of industrial chlorofluorocarbons deplete the ozone layer.

A haslong appeared that it was immune from

B haslong appeared to have been immune from

C haslong appeared as being immune to

D hadlong appeared immune to

E hadlong appeared that it was immune to

想了解这道题为什么正确选项要有过去完成时出现？求大神粗线~~谢谢~~

leohhy

Ozone,a special form of oxygen that screens out harmful ultraviolet rays, reaches high concentrations twelve miles above Earth, where it has long appeared that it was immune from human influence; we have now realized, though, that emissions of industrial chlorofluoro carbons deplete the ozone layer.


A has long appeared that it was immune from
>>>wrong idiom, appear immune to sb.; wrong tense
B has long appeared to have been immune from
>>>wrong idiom, appear immune to sb.; wrong tense
C has long appeared as being immune to
>>> wrong idiom, appear immune to sb.; wrong tense
D had long appeared immune to
>>>correct.
>>>The context tells us that the idea Ozone is immune to human influence is wrong. That's the reason past perfect tense is used.
E had long appeared that it was immune to
>>>wrong idiom, either to use "it(logical subject) appears that..." or " appear adj. to sb./sth."

lainemai

leohhy 发表于 2014-10-16 19:49
Ozone,a special form of oxygen that screens out harmful ultraviolet rays, reaches high concentration ...

context并没有tells us。。。是错的啊，你从哪里看出来的啊？

leohhy

lainemai 发表于 2014-10-16 20:03
context并没有tells us。。。是错的啊，你从哪里看出来的啊？

， context这整句话是我讲给你听的，不是原文的话。
原文“we have now realized, though, that emissions of industrial chlorofluorocarbons deplete the ozone layer.“，从now realized，though，这些词可以知道，第一句话的内容现在已经不成立了。

lainemai

leohhy 发表于 2014-10-16 20:37
， context这整句话是我讲给你听的，不是原文的话。
原文“we have now realized, though, that emissi ...

不是啦，我的意思是说你后面的话。。。在原文没有体现啊，没有体现immune to human是错的啊

leohhy

lainemai 发表于 2014-10-17 15:30
不是啦，我的意思是说你后面的话。。。在原文没有体现啊，没有体现immune to human是错的啊
...

第一句话说了Ozone ....immune to human influence;
第二句话说了industrial carbons deplete the ozone layer.
这不是清晰的告诉我们其实Ozone并不immune to human influence么？