Answer
Bronsted-Lowry Acid: $H_3O^+(aq)$
Bronsted-Lowry Base: ${HSO_3}^{-}(aq)$
Conjugate Acid: $H_2SO_3(aq)$
Conjugate Base: $H_2O(l)$
Work Step by Step
${H_3O}^+(aq) + H{SO_3}^-(aq) H_2{SO_3}^{}(aq) + H_2O(l)$
Since $H_3O^+$ donates one proton, it is the acid;
Since $H{SO_3}^-$ receives one proton, it is the base;
$H_2O$ is the conjugate base because it is the acid ($H_3O^+$) after donating a proton
$H_2SO_3$ is the conjugate acid because it is the base ($H{SO_3}^-$) after receiving a proton.
