求助：prep1-1

zhangjinjing

1.    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 (D)  

(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

解释上说suppliers are growing 与their natural growth rate不平行，与they grow naturally 平行，但是我不懂为什么与后者平行？

请大家帮我解答一下，不甚感激！

uustar

平行要求前后结构相同，suppliers are growing是主谓搭配，their natural growth rate是名词，所以不平行。they grow naturally也是完整的主谓结构。 

zhangjinjing

哦，原来是这样，谢谢哈