OG71

71. The original building and loan associations were organized as limited life funds, whose members made monthly payments on their share subscriptions, then taking turns drawing on the funds for home mortgages.

(A)  subscriptions, then taking turns drawing

(B)  subscriptions, and then taking turns drawing

(C)  subscriptions and then took turns drawing

(D)  subscriptions and then took turns, they drew

(E)   subscriptions and then drew, taking turns

The sentence speaks of a sequence of actions in the past:

shareholders made their monthly payments and subsequently took turns drawing on the funds. Choice C, the best answer, uses parallel past-tense verb forms to express this sequence. Choices A and B violate parallelism by using taking where took is required. The wording in D results in a run-on sentence and does not specify what the members took turns doing. Similarly, E does not specify what the members drew, and taking turns produces nonsense when combined with the rest of the sentence.

我看不懂解释……为什么D是错的呢，还有run-on是什么意思……

谢谢…………

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有类似的，楼上的朋友看看，然后总结，说给大家听听。