[20 kinds of common sense that Chinese must know].
First, the foundation. 
1.The order in which the colors of the rainbow are fixed as red, orange, yellow, green, blue, indigo, violet, due to the refraction of water droplets in the air and the fixed order of reflected light.
2.The human body is made up of about 60% water, which is excreted in the form of sweat, urine, and tears, so it needs to be replenished enough water every day to maintain the normal functioning of the body.
3.Plants convert light energy into chemical energy through photosynthesis and produce oxygen. It is necessary for humans and other animals to breathe.
4.The internal structure of the Earth consists of the Earth's crust, mantle, outer core, and core, with the crust being the outermost layer of solid rock on the Earth.
5.The solar system is composed of the Sun and eight planets, of which the Sun is the central celestial body, and the eight planets are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune in descending order of distance from the Sun.
6.China's four major inventions, including papermaking, printing, the compass, and gunpowder, have had a profound impact on the development of world culture.
7.The Seven Wonders of the World include the Pyramids of Egypt, the Hanging Gardens of Babylon, the Temple of Artemis in Turkey, the Sun God of Rhodes in Ancient Greece in the Mediterranean, the Lighthouse of Alexandria in Ancient Egypt, the Statue of Zeus in Olympia in Greece, and the Mausoleum of Mausolus in Turkey.
2. History and culture.
8.The order of Chinese historical dynasties is: Xia, Shang, Western Zhou, Eastern Zhou (Spring and Autumn Period and Warring States Period), Qin, Han, Three Kingdoms Period (Wei, Shu and Wu), Jin (Western Jin and Eastern Jin Dynasty), Northern and Southern Dynasties, Sui, Tang, Five Dynasties and Ten Kingdoms, Song, Yuan, Ming, and Qing.
9.The four great Chinese novels include Dream of the Red Chamber, The Water Margin, Journey to the West, and Romance of the Three Kingdoms, which are treasures of ancient Chinese literature.
10.The four masters of ancient Chinese poetry refer to Li Bai, Du Fu, Bai Juyi, and Liu Yuxi, whose works occupy an important place in the history of Chinese literature.
11.The fathers of ancient Chinese scientific and technological inventions were Cai Lun of papermaking, Bi Sheng of printing, Shen Kuo of compass and Sun Simiao of gunpowder.
12.The famous philosophers of ancient China, Laozi, Zhuangzi and Mencius respectively put forward Taoism, Moism, and Confucianism, which had a profound impact on the development of Chinese culture.
13.In traditional Chinese culture, "qin, chess, calligraphy and painting" refers to playing the qin, playing chess, calligraphy and painting, and these four skills are one of the necessary cultivation of ancient Chinese literati.
14.Traditional Chinese festivals include the Spring Festival, Qingming Festival, Dragon Boat Festival and Mid-Autumn Festival, which have a long history and profound cultural connotations.
III
15.With a population of about 1.4 billion, China is the largest in the world.
16.The official language of China is Mandarin, while dialects vary from region to region, including northern dialects, southern dialects, etc.
17.China's administrative divisions are divided into four levels: provinces, cities (prefecture-level cities), counties (county-level cities) and townships (towns), while autonomous regions and municipalities directly under the central government are provincial-level administrative divisions.
18.China is one of the largest developing countries in the world, and its economic strength has been increasing, and it has become one of the world's important economies.
19.China is rich in natural resources, including coal, oil, iron ore and other mineral resources and water resources, and is also one of the world's largest agricultural producers.
20.China is a multi-ethnic country, with 56 ethnic groups constituting the big family of the Chinese nation. China** has always been committed to promoting unity and development among all ethnic groups.