Tag Archives: explanation text

The Blue Sky: Reading Practice 9 (explanation)

By | December 6, 2017

It is easy to see that the sky is blue. Have you ever wondered why? A lot of other smart people have, too. And it took a long time to figure it out! The light from the Sun looks white. But it is really made up of all the colors of the rainbow. You learn that the light… Read More »

Underwater Earthquakes: Reading Practice 7 (explanation)

By | December 9, 2017

The most common causes of tsunamis are underwater earthquakes. To understand underwater earthquakes, you must first understand plate tectonics. The theory of plate tectonics suggests that the lithosphere, or top layer of the Earth, is made up of a series of huge plates. These plates make up the continents and sea floor. They rest on an underlying viscous… Read More »

Geyser: Reading Practice 4 (explanation)

By | December 22, 2017

A geyser is the result of underground water under the combined conditions of high temperatures and increased pressure beneath the surface of the earth. Since temperature rises approximately 1 F for every sixty feet under the earth’s surface, and pressure increases with depth, the water that seeps down in crack and fissures until it reaches very hot rock… Read More »

Floods: Reading Practice 2 (explanation)

By | December 22, 2017

Floods are second only to fire as the most common of all natural disasters. They occur almost everywhere in the world, resulting in widespread damage and even death. Consequently, scientists have long tried to perfect their ability to predict floods. So far, the best that scientists can do is to recognize the potential for flooding in certain conditions.… Read More »

Silkworm Caterpillars: Reading Practice 1 (explanation)

By | December 22, 2017

Silkworms live for only two or three days after laying eggs. About 36,000 to 50,000 eggs are laid, and these are carefully stored at the silkworm farm until they are ready to hatch. The eggs hatch into caterpillars, which feed on mulberry leaves. Soon, the caterpillars are ready to spin their cocoons. Not all caterpillars can spin silk… Read More »