[stasm]

(Author of the blog post here.) Great question, thanks! Unicode defines six categories of plural forms: zero, one, two, few, many, and other. The names of these categories always appear in English. Unicode also maintains a collection of all mappings of numerical rules to these categories, for all languages supported by the CLDR. See http://www.unicode.org/cldr/charts/latest/supplemental/langu... for the mapping corresponding to the Czech grammar.

[Zenbit_UX]

Care to comment about how it might handle one bold word or a link mid sentence?

[stasm]

When Fluent formats translations, it returns simple strings (in the sense of primitive computer types). They can include markup which is parsed by a higher-level abstraction responsible for actually showing the translations somewhere in the UI. Take a look at https://github.com/projectfluent/fluent.js/wiki/DOM-Overlays in the experimental fluent-dom package, and their React equivalent, https://github.com/projectfluent/fluent.js/wiki/React-Overla....

[quelltext]

Ah, if this is building on top of existing rules / standards that makes total sense.