How do the four seasons change in a year?

We divide a year into four seasons: spring, summer, autumn and winter. Each season lasts for 3 months, of which summer is the hottest season, winter is the coldest season, and spring and autumn are in between.

Seasons have a great influence on what happens on the earth. In spring, animals are born and plants wake up. Summer is very hot, and children usually have winter holidays. We may go back to a relatively cool place for our holiday. Crops are usually harvested in late summer. In autumn, leaves change color and fall from trees. It's time for students to go back to school. It is very cold in winter, and it snows in many places. Some animals, such as bears, hibernate in winter, while others, such as birds, migrate to warmer climates.