n.拱顶石，(计划、论据的)主旨，基础

原形：keystone复数：keystones

Keystone is the central stone in an arch, which supports the entire structure.
基石是拱门中的关键石头，支撑着整个结构。
The new tax policy acts as the keystone of the government's economic reform plan.
新的税收政策作为政府经济改革计划的关键基石。
The preservation of biodiversity is the keystone to maintaining ecological balance.
生物多样性的保护是维持生态平衡的关键基石。
In this company, customer satisfaction is considered the keystone of their success.
在这家公司中，客户满意度被视为他们成功的关键。
The signing of the peace treaty was the keystone of the reconciliation process between the two nations.
签署和平条约是两国和解进程中至关重要的一步。
His research on climate change has become the keystone for understanding global warming.
他关于气候变化的研究已成为理解全球变暖的关键基础。
A stable government is the keystone to social stability and economic development.
稳定的政府是社会稳定与经济发展的重要支柱。
The keystone of any good education system is providing equal opportunities to all students.
任何好的教育体系的关键在于为所有学生提供平等的机会。
Trust is the keystone that holds strong relationships together, whether personal or professional.
信任是维系个人或职业关系牢固的关键要素。
The discovery of penicillin was the keystone in the development of modern antibiotics.
青霉素的发现是现代抗生素发展过程中的重要里程碑。