1?-['teacher'].    2?-['learner2'].    3
    4?-cannot_do(Tl,Tt,parent(warren,catherine),C).    5?-cannot_do(Tl,Tt,parent(warren,david),C).    6?-cannot_do(Tl,Tt,parent(warren,variable(child)),C).    7?-can_do(Tl,Tt,parent(variable(parent),variable(child)),C).    8
    9?-cannot_do(Tl,Tt,entropy_increases(variable(a),variable(b)),C).   10
   11?-cannot_do(Tl,Tt,t_member(f,[g,f,d,s,a]),C).   12?-cannot_do(Tl,Tt,t_member(e,[q,w,e,r,t,z,t,r,e,w,q]),C).   13?-cannot_do(Tl,Tt,t_member(variable(a),[g,f,d,s,a]),C).   14?-can_do(Tl,Tt,t_member(variable(a),variable(list)),C).   15
   16?-cannot_do(Tl,Tt,reverse([c,b,a],variable(c)),C).   17?-cannot_do(Tl,Tt,reverse([a,b,c],[c,b,a]),C).   18
   19?-what_cannot_do(Ls,Ts,Q <- Ans,[],F).
   20?-what_cannot_do(Ls,Ts,qsort([1,2],variable(a)) <- Ans,[],F).
   21?-what_cannot_do(Ls,Ts,qsort([2,1],variable(a)) <- Ans,[],F).
   22?-what_cannot_do(Ls,Ts,qsort([2,3,1],variable(a)) <- Ans,[],F).
   23?-what_cannot_do(Ls,Ts,qsort([3,2,1],variable(a))