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In Chinese text, 'common' spaces (U+0020, U+00A0, U+202F) very rarely occur, if at all. The only spaces that do occur frequently are 'ideographic spaces' U+3000, often two of them (sometimes more, but Brill limits this to a pair of them) marking a paragraph indent. Such spaces must, of course, remain. Spacing near punctuation marks, quotation marks, and some other symbols is normally handled by adjusting white space in these characters themselves when a font is created, in left and/or right sidebearings, so any urge to adjust such spacing in a page layout application must be resisted.

Chinese spaces and punctuation marks are found in the Unicode ranges CJK Symbols and Punctuation and Halfwidth and Fullwidth Forms, among the 'Fullwidth ASCII variants'. The W3C provides a handy list.

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