Premise: The Cyrillic alphabet is an alphabet used for several East and South Slavic languages; (Belarusian, Bulgarian, Macedonian, Russian, Rusyn, Serbian, and Ukrainian) and many other languages of the former Soviet Union, Asia and Eastern Europe. It has also been used for other languages in the past. Not all letters in the Cyrillic alphabet are used in every language which is written with it.
Hypothesis: Cyrillic is an alphabet used for certain Slavic languages, such as Russian.
Label: YES