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：

until用在否定句中，为了强调时间状语，常用倒装语序。将否定副词not移到until的前面，主句的谓语动词由否定式转变为肯定句，在主语之前加助动词，构成主谓倒装。