Cyclohexylene
[建] 环己撑
🗣️ 情景例句
Hello.
哈啰。
Why did't you ask me?
为什么你不问我？
Up to now, historians have assumed that calendars came into being with the advent of agriculture, for then man was faced with a real need to understand something about the seasons.
历史学家迄今认为日历是随农业的问世而出现的，因为当时人们面临着了解四季的实际需要，