Today, the use of the genitive case is relatively rare in spoken language - speakers sometimes substitute the dative case for the genitive in conversation. But the genitive case remains almost obligatory in written communication, public speeches and anything that is not explicitly colloquial, and it is still an important part of the (language of education). Television programs and movies often contain a mix of both, dative substitution and regular genitive, depending on how formal or "artistic" the program is intended to be. The use of the dative substitution is more common in southern German dialects, whereas Germans from northern regions (where Luther's Bible-German had to be learned like a foreign language at that time) use the genitive more frequently. Though it has become quite common not to use the genitive case when it would formally be required, many Germans know how to use it and generally do so. Especially among the higher educated, it is considered a minor embarrassment to be caught using the dative case incorrectly. So it is not typically recommended to avoid the genitive when learning German: although the genitive has been gradually falling out of use for about 600 years, it is still far from extinct. The historical development of the has to some extent re-established the genitive into the language, and not necessarily just in written form. For example, the genitive is rarely used in colloquial German to express a possessive relation (e.g. "my father's car" may sound odd to some Germans in colloquial speech), but the partitive genitive is quite common today (e.g. "one of the best"). Furthermore, some verbs take the genitive case in their object, but this is often ignored by some native speakers; instead, they replace these genitive objects with (substitutional) prepositional constructions: e.g. ("I'm ashamed of you.") turns into (or )." ("I'm ashamed because of you.").