The first step is to create a directory like "zh_tw" in the "languages" directory, and then copy the web.lang.php file under zh_cn to this directory

The second step is to log in to the DouPHP backend, and in "System Settings" -> "System Language", select the language you just added

Note: As even the English version of the website backend used in China is in Chinese, the language switching of the backend is temporarily not available