The little snail asked her mother, why do I have to carry that hard and heavy shell since I was born? His mother told him that because our bodies have no bones to support us, we can only crawl, but not very fast, so we need to be protected by a shell. The little snail didn't understand and asked, Sister Caterpillar has no bones and can't crawl fast. Why doesn't she have to carry a hard and heavy shell? Mom said that because Sister Caterpillar can turn into a butterfly, the sky will protect her. The little snail was unwilling to give in and asked again, "The earthworm brother has no bones to crawl fast and can't turn into a butterfly. Why doesn't it carry a hard and heavy shell?" Mom said, because the earthworm brother can drill into the soil, the earth will protect it. The little snail cried, why doesn't the sky protect me and the earth doesn't protect me... The mother snail comforted him and said, so, we have shells, we are on our own. "
Although the snail's shell is not hard, in the snail's heart, its shell is the world and the only thing that can protect it from wind and rain.