pls help me i am beginner pls help in getting it



?- everyother([3,4,11,0,9,19],X).

X = [3, 11, 9] ;

No
?- everyother([2,99,3,4,11],YY).

YY = [2, 3, 11] ;

No
?- everyother([33],Y).

Y = [33] ;

No
?- everyother([],ZZZ).

ZZZ = [] ;

No
?- everyother(A,[4,5,6,7]).

A = [4, _G234, 5, _G240, 6, _G246, 7] ;

A = [4, _G234, 5, _G240, 6, _G246, 7, _G252] ;

No
?- everyother(A,[]).

A = [] ;

No
?- everyother(A,[b]).

A = [b] ;

A = [b, _G216] ;

No
?-
Note: If you are getting the correct answer more than once when you
press the semicolon, see if you can remove some cases from your file.
Redundant cases can create multiple paths to the same solution.

.