
Some animals take long naps. Hibernation is when animals sleep for a long time during winter. Groundhogs hibernate. They dig deep burrows under the ground. They stay safe and warm in their burrows.
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About 20,000 years ago, ice covered much of Earth. Temperatures … read more
Look at this bridge! This bridge helps people cross a river. It … read more
The Winter Olympics and Paralympics begin this February. These are … read more
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