2. The narrow sense of Central Asia, according to the definition of middle school textbooks in Chinese mainland and Taiwan Province Province, only includes five Central Asian countries: Kazakhstan, Uzbekistan, Tajikistan, Kyrgyzstan and Turkmenistan. The official definition of the Soviet Union only includes Uzbek Soviet Socialist Republic, Tajik Soviet Socialist Republic, Kyrgyz Soviet Socialist Republic and Turkmen Soviet Socialist Republic. The official names of the Soviet Union are Central Asia and Kazakhstan. Another definition is: in addition to the five Central Asian countries, it also includes southern Russia.
Broadly speaking, according to the definition of UNESCO, there are seven countries in Central Asia, namely, Afghanistan, China, India, Iran, Mongolian People's Republic, Pakistan and Soviet Union. As far as China is concerned, Xinjiang Uygur Autonomous Region, Xizang Autonomous Region, Qinghai Province, Hexi Corridor, Ningxia Hui Autonomous Region and Inner Mongolia Autonomous Region all belong to Central Asia.