How do you determine conjugate acid-base pairs?

Simply exchange a proton, ${H}^{+}$, and conserve mass and charge.
Do not be intimidated by this sort of question. All we are doing is taking the starting formula, $H X$, ${H}_{2} S {O}_{4}$, $H N {O}_{3}$, or even $H C {O}_{3}^{-}$, and removing a proton, ${H}^{+}$, to form the conjugate bases, ${X}^{-}$, $H S {O}_{4}^{-}$, $N {O}_{3}^{-}$, and $C {O}_{3}^{2 -}$ . As with all such chemical reactions, both MASS and CHARGE are conserved.
If I switch the solvent to ammonia, $N {H}_{3}$, rather than water, what is the conjugate base of ammonia in solvent of ammonia (i.e., here $N {H}_{3}$ takes on the role of ${H}_{2} O$)? What is the conjugate acid? I could even switch the solvent to an acidic solvent such as $H F$, or ${H}_{2} S {O}_{4}$. What are the conjugate acids in these solvents?