The "Storm Glass", a weather forecaster from 17th century Europe, indicates that when the liquid in the bottle is clear, it means the weather is fine; when the liquid in the bottle is turbid, it means the sky is cloudy and gloomy; when large crystals appear in the bottle, it means the temperature will drop or even snow. Give it to him/her so that he/she can always keep an eye on the weather and know whether it is cold or warm.