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kaijen
- Junior | Next Rank: 30 Posts
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Test2-8.
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 chlorofluorocarbons deplete the ozone layer.
(A) has long appeared that it was immune from
(B) has long appeared to have been immune from
(C) has long appeared as being immune to
(D) had long appeared immune to
(E) had long appeared that it was immune to
Ans: [spoiler](D)[/spoiler]
I chose[spoiler] (B)[/spoiler]
What's the difference between immune from and immune to ?
Why should I use past perfect tense here?
thx
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 chlorofluorocarbons deplete the ozone layer.
(A) has long appeared that it was immune from
(B) has long appeared to have been immune from
(C) has long appeared as being immune to
(D) had long appeared immune to
(E) had long appeared that it was immune to
Ans: [spoiler](D)[/spoiler]
I chose[spoiler] (B)[/spoiler]
What's the difference between immune from and immune to ?
Why should I use past perfect tense here?
thx












