float ring

例句：

1. 1. The boat's keel is a floating ring that keeps it stable in the water.
   船的龙骨是一个浮动环，它在水中保持船的稳定性。
2. 2.The engineer designed a floating ring to support the weight of the cargo.
   工程师设计了一个浮动环来支撑货物的重量。
3. 3. The scientist used a floating ring to measure the density of the water.
   科学家使用一个浮动环来测量水的密度。