  Recently, Ni and Pan proved a $q$-congruence on certain sums involving
central $q$-binomial coefficients, which was conjectured by Guo. In this paper,
we give a generalization of this $q$-congruence and confirm another
$q$-congruence, also conjectured by Guo. Our proof uses Ni and Pan's technique
and a simple $q$-congruence observed by Guo and Schlosser.
