For documents that contain Unicode characters beyond the ASCII range, the parser must read and convert multiple byte sequences for each character.

对于包含ASCII以外的Unicode字符的文档，解析器必须为每个字符读取和转换多字节序列。

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This encoding scheme makes it possible to encode an ASCII character with one byte, and a non-ASCII character with multiple (up to 4) bytes.

这个编码方案可以用一个字节对 ASCII 字符进行编码，用多个字节（最多 4 字节）对非 ASCII 字符进行编码。

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