Question

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

Answer 1

答案：A
解析：

not until位于句首引导时间状语，句子要倒装。D项否定词重复使用，故不正确。