Tell me how to explain expository text

Column numbers, for example: The earth is a planet with a radius of about 6400 kilometers.

Definition, for example: There is no second planet suitable for human habitation outside the area of ??4 billion square kilometers with the earth as the center.

For example, there are so many flowers in spring, including peach blossoms, pear blossoms, azaleas and so on.

For comparison, for example: Compared with the universe, the earth is really too small.

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