A fifth reason could be the change of standard spelling rules in the local language. When Pinyin was made the official romanization, or writing Mandarin Chinese using the Roman alphabet, in mainland China after the Chinese Communist Party took over, the spellings of many Chinese place names changed, including Peking becoming Beijing and Nanking becoming Nanjing. Even though the pronunciations of Chinese place names in Mandarin Chinese were not any different before the changing of spelling, the older spellings did not accurately show their pronunciation. Therefore, the pronunciation of Chinese place names in other languages, or their exonyms, were based on their spelling rather than the Mandarin pronunciation, which is why they sound so different from each other. In order to teach people how to correctly pronounce Mandarin Chinese, the CCP made Hanyu Pinyin the only accepted romanization in mainland China. Even though Taiwan also speaks Mandarin, the spellings of Taiwanese place names, including Taipei and Kaohsiung, is according to the older spelling rules for Chinese place names. This is because many Taiwanese do not want to use Hanyu Pinyin, even though it is the standard romanization of Mandarin Chinese worldwide, because it was created by the Communist Party of China.