(2020·湖北省黄冈市高三质量检测)Andit'sfastbecomingoneofthegreatestp...

问题详情：

(2020·湖北省黄冈市高三质量检测)And it's fast becoming one of the greatest public health challenges ________ we face in the 21st century.

【回答】

that　空格处引导定语从句，修饰先行词challenges，在从句中作宾语；由于先行词前有最高级the greatest修饰，所以只能用that引导。

知识点：定语从句

题型：阅读填空