Compliance in French

The eighteenth entry is le corpus de règles internes, and the noun at the front of it belongs to a small class worth learning as a class rather than one word at a time. French borrowed a handful of Latin nouns ending in -us without changing a letter, and it then declined to give them a French plural. Un corpus becomes des corpus, un campus becomes des campus, and the same holds for un consensus, un prospectus and un virus. Nothing is added and nothing is heard, so only the article moves. They are masculine as well, whatever they happen to name, because the ending and not the meaning decides. English went the other way and went back to Latin for the plural, which is why a careful writer still hesitates between « corpora » and « corpuses », says « campuses » without a second thought, and can argue about « data » all afternoon. The French phrase here is therefore easier than it looks: a firm with several rulebooks has des corpus de règles, spelt exactly as it was in the singular.