(1) L={null ,a ,b,aab,aaab,................}
L=Any number of a followed by any numbers of b
(2) Let us consider regular language L=0*1*
For example, 0*1* is regular, but its subset {On1n : n >= 0} is not regular, but its subset {01, 0011, 000111} is regular again.
For super set Not necessarily regular (take $\Phi$ is regular )
So we can say subset /superset of regular language need not be regular.
Regular languages are not closed under the subset/superset relation.