水蒸气

例句：

1. 1. The hot air rises and condenses into water droplets.
   热空气上升并凝结成水滴。
2. 2. The greenhouse uses a system of glass walls to trap the water vapor.
   温室使用玻璃墙系统来捕获水蒸气。
3. 3. The scientist observed that the water vapor was rising from the bottom of the tank.
   科学家观察到水蒸气正从水箱底部升起。