over & during

nina23

866.    Tiny quantities of more than thirty rare gases, most of them industrial by-products, threaten to warm the Earth’s atmosphere even more rapidly than carbon dioxide during the next fifty years.
(A) to warm the Earth’s atmosphere even more rapidly than carbon dioxide during the next fifty years
(B) to warm the Earth’s atmosphere even more rapidly over the next fifty years than carbon dioxide will
(C) during the next fifty years to warm the Earth’s atmosphere even more rapidly than carbon dioxide
(D) a warming of the Earth’s atmosphere during the next fifty years even more rapid than carbon dioxide’s
(E) a warming of the Earth’s atmosphere even more rapid than carbon dioxide’s will be over the next fifty years

请问A和B中的 during the next fifty years/over the next fifty years在用法上有区别么，记得以前做过OG一道好像是没有区别，
220.    For almost a hundred years after having its beginning in 1788, England exiled some 160,000 criminals to Australia.
(A) For almost a hundred years after having its beginning in 1788,
(B) Beginning in 1788 for a period of a hundred years,
(C) Beginning a period of almost a hundred years, in 1788,
(D) During a hundred years, a period beginning in 1788,
(E) Over a period of a hundred years beginning in 1788,

dreadpower

我也有同样的疑惑

bluestone1

866 的关键在 补出will, 以明确比较对象不是 the Earth’s atmosphere； during / over 好像关系不大

Snazzy

866
1, I agree with Bluestone on the use of over/during in this sentence. They don't really matter.
2, The meaning is slightly changed when 'over ...years' is positioned after.
3, 'will' is the key point to choose the right answer.

220, I sensed 'over' has a meaning of 'from ... to...', kind of progress, while 'during' is just a span of a period. (ANY COMMENT IS WELCOMED)