Think of your immune system as your personal bodyguard, always alert for trouble. It immediately res
[794호]
Fossils are the remains or impressions of things that lived long ago. An animal or plant must be bur
[793호]
Evolution is a process where living things change over time to survive in their environment. For exa
[792호]
Human rights are things that everyone has a claim to, no matter who they are or where they live. For
[791호]
Color is a perception of the wavelengths of light that bounce off an object and reach our eye. Objec
[790호]
Gravity is an invisible force that pulls objects toward each other. It keeps us on the ground and pl
[789호]
The universe is roughly 13.8 billion years old ? a number so enormous it’s hard to imagine! Scie
[788호]
New Year celebrations have been around for thousands of years! A long time ago, the people of Mesopo
[787호]
Hibernation is how some animals survive the winter. It’s not the same as sleeping. During hibernat
[786호]
Researchers in the U.S. experimented to see whether artificial intelligence
[729호]
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