水汽现象

例句：

1. 1. The air isso dry that it can cause water vaporto condense into clouds.
   空气如此干燥以至于它可以导致水汽凝结成云。
2. 2.The scientist observed the formation of water vaporin the atmosphere.
   科学家观察到大气中水汽的形成。
3. 3. The phenomenon of water vapor condensing into clouds is known asevaporation.
   水汽凝结成云的现象称为蒸发。