Because of the corrosion phenomenon caused by oxidation reaction, iron cans will rust and rot when buried in soil for a long time, while pottery cans are less affected by oxidation reaction and can be preserved for many years.

Pottery and Tin Pot is a textbook compiled in the second volume of Grade Three. The story is about the self-reliance of the tin pot in "The Chef of the King" and the disdain for the pottery pot. After being buried in the soil for many years, the pottery jar was unearthed as a cultural relic, but the iron jar turned into soil and no longer existed.

This story tells us that everyone has strengths and weaknesses. We should be good at seeing the advantages of others and face up to our own shortcomings. We can learn from each other's strengths, but we don't need to belittle ourselves, respect each other and live in harmony.