domains list=symbol* predicates con(list,list,list) clauses con([],L1,L1). con([X|Tail],L2,[X|Tail1]):- con(Tail,L2,Tail1). OUT PUT ======= Goal: con([a,b,c],[d,e],ConcatList) ConcatList=[\"a\",\"b\",\"c\",\"d\",\"e\"] 1 Solution