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buyiting

To meet the rapidly rising market demand for fish and seafood, suppliers are growing fish twice as fast as their natural
growth rate, cutting their feed allotment by nearly half and raising them on special diets.
(A) their natural growth rate, cutting their feed allotment    
(B) their natural growth rate, their feed allotment cut  
(C) growing them naturally, cutting their feed allotment    
(D) they grow naturally, cutting their feed allotment    
(E) they grow naturally, with their feed allotment cut
答案D 。请问， as fast as 前后应是对比的，但是我如何能看出来as......as后的形式应该是什么样的呢？请以此题为例给小女子讲下吧。跪求啦。

coolhaoming

这个说suppliers养鱼生长的速度是鱼自然生长速度的两倍。这个they应该指鱼，因为最后一句raising them on speical diets里的them指的就是鱼。从意思上来说D更好