Prolog: show DCG problems

1 files changed, 1 insertions, 1 deletions

diff --git a/prolog/problems/dcg/ab_2/en.py b/prolog/problems/dcg/ab_2/en.py
index 53f9e9a..9a709b1 100644
--- a/prolog/problems/dcg/ab_2/en.py
+++ b/prolog/problems/dcg/ab_2/en.py
@@ -4,6 +4,6 @@ slug = 'a*b*'
 description = '''\
 <p>Write a DCG with the starting symbol <code>ab</code> for the language <code>a<sup>m</sup>b<sup>n</sup></code>, where m, n ≥ 0.</p>
 <p>Example words: <code>[]</code>, <code>a</code>, <code>aab</code>, <code>abbb</code>, <code>bbb</code>.</p>
-<p>Hint: to generate words of increasing length, use the query <code>conc(Word,_,_), ab(Word,[])</code>.</p>'''
+<p>Hint: to generate words of increasing length, use the query <code>append(Word,_,_), ab(Word,[])</code>.</p>'''
 
 hint = {}