"Fire Clouds", "Golden Grass", "Beauty of Four Seasons".

1. "Fire Clouds" is a lecture text in the seventh unit of the second volume of the third grade edition. It describes to readers the changes in color and shape of the fire cloud from up to down after dinner. Changes in color and shape are emphasized.

2. The main writer of "Golden Grass" and his younger brother often played on the grass, and discovered two things: the changes in the color of the grass and the reasons for the changes.

3. The first paragraph of "The Beauty of Four Seasons" describes the sky at dawn in spring, using "fish belly color, red stripes, red, purple, red and purple" to describe the changes in the color of the sky.