Not until all the fish died in the river how serious the pollution was.
A. did the villagers realize
B. the villagers realized
C. the villagers did realize
D. didn't the villagers realize
网友回答
(答案→)A. did the villagers realize
B. the villagers realized
C. the villagers did realize
D. didn't the villagers realize
解析：考查倒装句。Not until放在句首时，后面的主句使用部分倒装句。结合句意可知A正确。句意：直到河里所有的鱼都死了，村民们才意识到污染是多么的严重。