keystone
n
1 (architecture 建) central stone at the top of an arch locking the others into position 拱顶石.
2 (usu sing 通常作单数) (fig 比喻) most important part of a plan, an argument, etc on which all the other parts depend (计划、 论据等的)基础, 主旨
Belief in a life after death is the keystone of her religious faith. 她的宗教信仰的基础是相信死後有来生. Cf 参看 corner-stone (corner1).
🗣️ 情景例句
Let's talk business.
我们来谈谈正经事。
We put pressure on the government to change this law.
我们给政府施加压力,要求修改那条法律。
when he knew that he was dying, he made me promise to go on my own.