Language and Content
Success in Science
Learn About Cycles
A cycle is a series of events that happen again and again.
A diagram is a drawing. It can show how a cycle works.
LIFE CYCLE OF A BEETLE
title
eggs
adult beetle
larva
pupa
label
Study the diagram and listen to the article. Then do the Review.
• How does the water cycle work?
The Earth’s water can take many forms. It can be a liquid, like rainwater, or a solid, like ice.
rain
ice
It can even take the form of vapor. You cannot see vapor. When water boils, it turns to water vapor.
The Earth’s water is recycled. Heat from the sun turns water on the Earth into water vapor. This process is called evaporation. The water vapor is carried up by the air. Air that is full of water vapor can cool off. When this happens, clouds form and the water vapor turns into water again. The water falls from the clouds as rain or snow, for example, and becomes part of the water on Earth. Some of this water—in rivers and lakes, for example—evaporates, and the cycle begins again.
THE WATER CYCLE
1. Check Your Understanding Tell in your own words how the water cycle works. Use the diagram.
2. Vocabulary Give an example of another cycle.
3. Use Diagrams Draw a diagram to show how another cycle works.