title: Problem in performing translation of list of numbers to words such as [1,2,3] to [one,two,three]
body: <p>Hello everyone I am trying to translate numbers to list of words. My logic seems to be correct but there is something wrong with the output. I am using swi-prolog in my Mac.</p>
  
  <p>So when I enter 
  translate([1,2,3],X).
  it gives false.</p>
  
  <pre><code>means(0,zero).
  means(1,one).
  means(2,two).
  means(3,three).
  means(4,four).
  means(5,five).
  means(6.six).
  means(7,seven).
  means(8,eight).
  means(9,nine).
  
  translate([],[]).
  translate([Head|Tail],[Head1|Tail1]):-
     means(Head,Head1),
     translate(Tail,Tail1).
  </code></pre>
  
  <p>Expected:</p>
  
  <pre><code>?- translate([1,2,3],X).
  X = [one,two,three].
  </code></pre>
  
  <p>But got:</p>
  
  <pre><code>?- translate([1,2,3],X).
  false.
  </code></pre>