我爱科学

The planet we live on is called earth. It is special （ 特别的） in the universe（宇宙） because it has life on it. It moves around the sun so we call it a planet（行星）.Our home planet is a rocky one （石质行星）.Our rocky planet has water.Water covers about 70% of its surface（表面）.That＇s why the Earth looks blue from space.     

Rainbows

We are all happy to see a rainbow in the sky. Beautiful rainbows look like seven-color bridges in the sky. Rainbows sometimes appear （出现） in pairs（成对） . Have you ever thought about where rainbows come from？ When can we see them？ Why do rainbows usually appear after it rains？