/*
member(X,Y):-Y=[X|_].
:-consult(lib.pl).
*/
member(X,[X|_]).
member(X,[_|T]):-member(X,T).


in(X,[X|_]).
in(X,[_|T]):-in(X,T).

:-op(800,xfx,in). 

engFre(Ew,Fw):-trans(Ew,Fw) in 
[trans(book,livre),
trans(man,homme),
trans(apple,pomme)].

/*****/
:-op(800,xfx,[has,isa,flies]).

Animal has hair :- Animal isa mammal.
Animal has feathers :- Animal isa bird.
owl isa bird.
dog isa mammal.
cat isa mammal.

/***/
:-op(300,xfx,likes).
:-op(200,xfy,and).

susan likes piano and tennis and soccer.
/*
likes(susan,and(piano,and(tennis,soccer))).
*/