When it comes to toilets, you will think that it is a foreign country, but people are local products. The ancient toilet was really a bucket. There is also a domineering name, "nothing". Unfortunately, when the Tang Dynasty came, Tang Gaozu's grandfather was also called nothing and Li Hu.
Must change! Later, "Nothing" was renamed "Horse". The earliest "horse" was suitable for men. In order to let women use the "horse", the "horse" was enlarged into a circle and covered with a secret cover, so it was renamed as "toilet" until today.
Not only the toilet, there are always some problems. I don't think there is any problem at ordinary times, but when I think about it, I don't think it's right. Seriously, that's because a man named John Makadan improved the method of building roads at that time, so he named this road after him. Therefore, "Dao" is actually the abbreviation of "Macadan Dao", which has nothing to do with horses.
In the18th century, paper and ink were very precious. If you can't afford it in class, use cheap erasable slate instead. So, the blackboard was indeed black at that time. In the 20th century, people began to beautify the blackboard, thinking that green is softer and more eye-protecting. So the blackboard was replaced by a green board. China generally uses "standing like a cabinet, lying like a box" to distinguish between boxes and cabinets. Later, the refrigerator was introduced to China, but it opened horizontally on its side, but its function was the same as ours. At this time, it is not used to changing its name to refrigerator, which is called refrigerator.