keystone例句
Quantitative measurements of one sort or another serve as the
keystone of engineering practice.
定量测定一种或多种成分是环境工程中的重要项目.
The
keystone to any marriage is one word: " WE ".
任何婚姻的基石只有两个字: “ 我们 ”.
Advancing suburban assurance is the difficulty and
keystone of domestic insurance enterprise.
发展农村保险是我国保险业发展的难点和重点.