Consider the following acid-base equilibrium:
HCO_(3)^(-) HCNLongleftrightarrowH_(2)CO_(3) CN^(-)
In the reaction above, the Brönsted-Lowry bases are
HCO_(3)^(-) CN^(-)
HCO_(3)^(-) HCN
H_(2)CO_(3) CN^(-)
HCN H_(2)CO_(3)