English translation for aunt/2 added.

1 files changed, 77 insertions, 2 deletions

diff --git a/prolog/problems/family_relations/aunt_2/en.py b/prolog/problems/family_relations/aunt_2/en.py
index 4314a7a..f8bf35b 100644
--- a/prolog/problems/family_relations/aunt_2/en.py
+++ b/prolog/problems/family_relations/aunt_2/en.py
@@ -7,6 +7,81 @@ description = '''\
 ?- aunt(sally, X).
   X = vanessa ;
   X = patricia.
-</pre>'''
+</pre>
+<p><a target="_blank" href="[%@resource famrel.svg%]">Family trees</a> are
+described with predicates <code>parent/2</code>, <code>male/1</code>, and
+<code>female/1</code>.</p>
+'''
+
+plan = ['''\
+<p>Perhaps you can make use of the solution to one of the previous exercises?</p>
+<p><img src="[%@resource Prolog_aunt_06.svg%]" alt="My sibling has a child..." /></p>
+''', '''\
+<p>If <code>X</code> is a sister of the parent of <code>Y</code>,
+then <code>X</code> is the aunt of <code>Y</code>.</p>
+''', '''\
+<p><img src="[%@resource Prolog_aunt_07.svg%]" alt="A sister of Y's parent is the aunt of Y." /></p>
+''']
+
+hint = {
+    'x_and_y_mixed_up': '''\
+<p><code>X</code> should be the aunt of <code>Y</code>, not the other way around.</p>
+''',
+
+    'precedence_fail': '''\
+<p>Did you mix up the precedence of operators <em>or</em> & <em>and</em>?</p>
+<p>Operator <em>and</em> has higher precedence than operator <em>or</em>.
+If you wish to change that you can use brackets (as usual in mathematics).</p>
+''',
+
+    'x_must_have_sibling': '''\
+<p>An aunt usually has a sibling...</p>
+<p><img src="[%@resource Prolog_aunt_02.svg%]" /></p>
+''',
+
+    'x_must_be_female': '''\
+<p>An aunt is usually female.</p>
+<p><img src="[%@resource Prolog_aunt_05.svg%]" /></p>
+''',  # TODO: Loni should mark female gender on some aunt hints!
+
+    'y_must_have_parent': '''\
+<p>It would probably make sense if the nephew has a parent, right?</p>
+<p><img src="[%@resource Prolog_aunt_01.svg%]" /></p>
+''',
+
+    'aunt_vs_mother': '''\
+<p>How can an aunt also be the mother of <code>Y</code>?
+Did you forget to specify that an aunt and the parent of <code>Y</code> cannot be the same person?</p>
+<p><img src="[%@resource Prolog_aunt_04.svg%]" /></p>
+''',
+
+    'x_need_not_be_parent': '''\
+<p><code>X</code> doesn't need to have children to be somebody's aunt...</p>
+''',
+
+    'y_need_not_be_parent': '''\
+<p>A nephew <code>Y</code> doesn't need to have children...</p>
+''',
+
+    'nephews_parent_can_be_male': '''\
+<p>A parent of nephew <code>Y</code> can also be male
+(which means that this parent cannot be a sister of <code>X</code>).</p>
+''',
+
+    'predicate_always_false': '''\
+<p>It seems your predicate is <em>always</em> "false". Did you give it the correct name,
+or is it perhaps misspelled?</p>
+<p>If the name is correct, check whether something else is misspelled, perhaps there is a full stop instead of
+a comma or vice versa, or maybe you typed a variable name in lowercase?</p>
+<p>It is, of course, also possible that your conditions are too restrictive, or even impossible to satisfy
+(as would be, for example, the condition that <code>X</code> is both a parent and a sister of <code>Y</code>, or
+something similarly impossible).</p>
+''',
+
+    'interesting_tidbit': '''\
+<p>Interesting tidbit. This exercise could also be solved using the solution to the <code>sister/2</code>
+relation. An aunt is a sister of some parent of <code>Y</code>.</p>
+<p><img src="[%@resource Prolog_aunt_07.svg%]" /></p>
+''',    # TODO: only trigger if sister is not part of correct solution
+}
 
-hint = {}