It was not until 1920 ( ) American women had the chance to vote in national elections.为什么用that不能用when
问题描述：
It was not until 1920 ( ) American women had the chance to vote in national elections.
为什么用that不能用when
答
强调句式It is not until sometime that...对American women didn't have the chance to vote in national elections until 1920.进行强调,要把not until放在一起.这种强调句有一个固定的结构：It is...that,它不是...