完成这座标志性建筑是他职业生涯的巅峰成就。

Completing this iconic building was the ___capstone of his professional career.

工匠们将最后一块石头作为压顶石放在了金字塔的顶端。

The workers placed the final stone as the ___capstone on top of the pyramid.

他的毕业设计是这个工程学课程的顶点项目。

His senior design project was the ___capstone of this engineering program.