Rozumět

I have no proof, but I think the original object of Czech rozumět was expressed in the accusative, just as it still is in Polish, Serbo-Croatian, Slovenian and Ukrainian. The accusative with this verb has been preserved in the expressions nerozumět ani slovo (lit. to understand not even a word, with the object in the accusative), nerozumět ani slova (with an "old" genitive because of the negation, still kept in Polish, cf. Czech Mám dům and Nemám dům and Polish Mam dom and Nie mam domu, meaning I have a house and I don't have a house, respectively) and the maybe more modern nerozumět ani slovu.