Character is an errorcharacter and cannot be converted by the IME. For example, some consonants cannot be put together.
字符是一个错误的字符，不能被IME所转换。使用某些辅音字母不能放在一起。
2
If these characters are introduced, the user gets an error -20412, which corresponds to the XML white paper rule that serialization of an XML value must not inject a substitution character.
F truth is the recognition of the systematic character of a certain kind of error, then it would be fully dependent on the prior existence of this error.