How is the Belarusian language related to Russian and Ukrainian?

Belarusian, Russian, and Ukrainian are all members of the East Slavic language group. Historically, these languages were indistinguishable until the 12th or 13th century, following the fall of Kievan Rus.12

Belarusian serves as a linguistic link between Russian and Ukrainian. Its dialects do not have sharp boundaries; instead, they shade gradually into Russian dialects on one side and Ukrainian dialects on the other. While all three languages share a degree of mutual intelligibility, Belarusian is considered more closely related to Russian than Ukrainian is.342

The development of these languages has been shaped by distinct historical and cultural influences:
* Shared Features: All three are written in the Cyrillic alphabet.324
* Loanwords: Belarusian and Ukrainian share a significant number of Polish loanwords, whereas Russian contains more borrowings from Church Slavonic.32
* Historical Context: Belarusian was the official administrative language of the Grand Duchy of Lithuania from the 14th to 16th centuries.34