状语从句作插入语

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  问：This animal, _______ a great deal of time in water, does not feed in the water.

A. spend   B. they spend   C. although they spend   D. which they spend

请问到底该选哪个选项？

   答：应该选C。本句主语是This animal，谓语是does not feed。逗号之间的从句，显然是插入成分。A 和B不符合要求。D虽然表面上是非限定性定语从句，修饰前面的成分，但是which指主语，马上又接主语they，成了双主语，故应该排除。C是由连词although（尽管）引导的让步状语从句，作插入成分，完全符号条件，所以选C。