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Carbon monoxide levels in the atmosphere

Expert replies
by anksgmat » Wed Apr 15, 2009 4:45 am
Carbon monoxide levels in the atmosphere grew by enough
of an increased percentage during the twentieth century that it
began to trap heat radiating from the Earth, and it caused the
average surface temperature to rise.


· Carbon monoxide levels in the atmosphere grew by enough
of an increased percentage during the twentieth century
that it began to trap heat radiating from the Earth, and it
caused the average surface temperature to rise.
· Carbon monoxide levels in the atmosphere increased by
enough of a percentage during the twentieth century that
they began to trap heat radiating from the Earth, causing
the average surface temperature to rise.
· Levels of atmospheric carbon monoxide increased
sufficiently during the twentieth century to begin trapping
heat radiating from the Earth, causing the average surface
temperature to rise.
· Atmospheric carbon monoxide levels increased by a
sufficient percentage during the twentieth century to begin
trapping heat radiating from the Earth, which caused the
average surface temperature to rise.
· Levels of carbon monoxide in the atmosphere during the
twentieth century increased enough to begin trapping heat
radiating from the Earth, causing the average surface
temperature to rise.

OA - C. Which i found to be the correct option too.
But i have a doubt

[Levels of atmospheric carbon monoxide] increased
sufficiently [during the twentieth century] to begin
trapping heat radiating from the Earth, causing the average surface

Does this not cause a change of tense. I have such doubts in other SC too. Shouldn't the tense remain same.

How do i identify in such cases , please suggest :?
Winning is not every thing , its the only thing
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Source: — Sentence Correction |

Please help with this SC

by anksgmat » Sun Apr 19, 2009 9:39 pm
Hi Experts,

Please help me clear the confusion.

Regards
Anks
Winning is not every thing , its the only thing
Join the discussion

[Levels of atmospheric carbon monoxide] increased
sufficiently [during the twentieth century] to begin
trapping heat radiating from the Earth, causing the average surface

If you see inherent sense of tshi sentence it says that ... first--- the level of Carbon monoxide increased .. and second -- the efect of the increase--which is still continuiing ...

:) hope that makes sense too
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by veenu08 » Thu Jun 13, 2013 3:44 am
Hi,

Here I am facing meaning issue-
Levels of atmospheric carbon monoxide increased
sufficiently during the twentieth century to begin trapping
heat radiating from the Earth, causing the average surface
temperature to rise. -- subject is levels of atmospheric carbon monoxide, and verb- begin trapping is referring to levels or to carbon monoxide? IMO here it is levels, but shouldn't it be carbon monoxide?
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by veenu08 » Sat Jun 22, 2013 1:15 am
some please reply over my query
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