hourglass-shaped spring

例句：

1. 1. The hourglass-shapedspring is a fascinating mechanism that can beused to measure the passage of time.
   这个钟形弹簧是一个有趣的机制，可以用来测量时间的流逝。
2. 2. The hourglass-shaped springwas designed to help people remember important datesand events.
   这个钟形弹簧被设计用来帮助人们记住重要的日期和事件。
3. 3. Thehourglass-shaped spring was used asa tool for measuring the length of aperson's life.
   这个钟形弹簧被用作测量一个人寿命的工具。