Plants, animals, and people all need water to live. More than two-thirds of the human body is water. We must drink water every day to remain healthy. Harder - Water is a compound of two elements, hydrogen and oxygen. Each water molecule contains two hydrogen and one oxygen atoms.
Water can be liquid, solid, or gas.
It can evaporate into vapor or freeze into ice. Most of the Earth's surface is covered by water. The water cycle is the constant movement of this water. The water from rivers, lakes, and oceans evaporates into vapor. The vapor rises and forms clouds.