[填空题]The water cycle is a exciting and continuous process. 76. ______
The warm sun causes water on Earth to vapor, that is, 77. ______
to change into a gas and rise up into the sky. This is how forms 78. ______
clouds that float in the sky. Clouds can be mass of water droplets or 79. ______
ice particles. When the clouds get heavier enough, the water falls 80. ______
back to the earth. The water vapors must turn into a liquid or solid 81. ______
after it can fall to the earth. When the water falls back to the earth 82. ______
it is called precipitation. The water may fall in rain, snow, or hail. 83. ______
Plants in our environment also sends water vapor into the 84. ______
atmosphere. When plants do this it is called transpiration. 85. ______