Sentence Break - Extend
Extend is a character class used in text segmentation that includes combining marks, such as diacritics, and certain other nonspacing or spacing combining characters, as well as zero width joiner and some format characters. These characters do not start or end a sentence on their own; instead, they attach to the preceding base character and are kept together with it when determining sentence boundaries. This prevents a sentence from being split after a combining mark or before a following modifier, ensuring that grapheme clusters and their accompanying annotations remain intact for natural language processing and line breaking. The class effectively extends the scope of a preceding character so that punctuation or spaces following the extended sequence still correctly mark the sentence end.