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In addition to a spoken standard and a closely related written standard, Czech has several regional dialects primarily used in rural areas by speakers less proficient in other dialects or standard Czech. During the second half of the twentieth century, Czech dialect use began to weaken. By the early 1990s dialect use was stigmatized, associated with the shrinking lower class and used in literature or other media for comedic effect. Increased travel and media availability to dialect-speaking populations has encouraged them to shift to (or add to their own dialect) standard Czech. Although Czech has received considerable scholarly interest for a Slavic language, this interest has focused primarily on modern standard Czech and ancient texts rather than dialects. Standard Czech is still the norm for politicians, businesspeople and other Czechs in formal situations, but Common Czech is gaining ground in journalism and the mass media.

What is dialect use associated with and thus stigmatized because of?
lower class