21.Without ______ thorough understanding of great scientific achievements
问题描述：
21.Without ______ thorough understanding of great scientific achievements
Without ______ thorough understanding of greatscientific achievements,you can’t have ____ say over their positive effects onour life.
a；a 为什么?
答
这是两个固定说法而已：
a thorough understanding of .透彻地理解.
have a say over sth 对.的发言权