* China: Mandarin is the official language and spoken by the vast majority of the population.
* Singapore: Mandarin is one of four official languages in Singapore, alongside English, Malay, and Tamil.
* Taiwan: While the official language is called "Mandarin Chinese" or "Guoyu" in Taiwan, it differs slightly from the version spoken in mainland China.
It's important to note that Mandarin is spoken by significant communities in other countries as well, due to Chinese diaspora and immigration.