The central idea of "the footprint of time" in Class 8, Grade 8

The central idea of "Footprints of Time" in Class 8, Grade 8: Everything in nature will change with the passage of time, and so will human society. We should cherish time and gain more knowledge and wisdom to read the records of nature for the benefit of mankind.

The Footprint of Time is the text of the eighth lesson of the eighth grade junior middle school Chinese textbook (revised in the spring of 20 18). This article is a popular science work, the main task of which is to introduce the peculiar function of rocks to record time, aiming at explaining the significance of understanding this peculiar function of rocks and inspiring the enthusiasm of young people to explore the mysteries of nature.

The title of the article "Footprints of Time" is borrowed from Gao Shiqi's poem "Uncle Time". The use of personification vividly shows the traces of time hidden in rocks of various shapes and sizes, so as to arouse people's desire for exploration and interest in reading.

notes to a text

1. Trace: the trace left by the action.

2. The seas run dry and the rocks crumble: It takes a long time for the seas run dry and the rocks crumble.

3. Corrosion: ① The object is gradually damaged by chemical action; ② People gradually degenerate under the influence of bad thoughts, behaviors, environment and other factors. (① is used in this article)

4. Foothill: the part where the hillside meets the surrounding flat land.

5. Roughness: (material) is not fine or smooth.

6. Cracking: Cracking many joints.

7. planing: leveling.