Prolog concate function

%conc(L1,L2,List) - adds list L2 to L1 and returns L3 
%- example conc([b,c],[a,b,e],X). X = [b,c,a,b,e]
conc([],L,L).

conc([X|L1],L2,[X|L3]):-
 conc(L1,L2,L3).