Question

Not until all the fish died in the lake __________ how serious the pollution was.

A．did the villagers realize	B．the villagers realized
C．realized the villagers	D．do the villagers realize

Answer 1

A

试题分析：句意：直到湖里所有的鱼都死了，村民才意识到污染多严重。Not until+从句放在句首的时候，后面的主句要部分倒装，助动词放在主语前面，排除BC，因为前面用died，所以用一般过去式，选A。