【简答题】One day, a boy found the cocoon(茧) of a butterfly and brought it home. A few days later, the boy saw a small ___31___ in the cocoon. He sat and watched for several hours as a butterfly struggled to ma...
【简答题】One day, a boy found the cocoon(茧) of a butterfly and brought it home. A few days later, the boy saw a small 36 in the cocoon. He sat and watched for several hours as a butterfly struggled to make 37 ...