diff --git a/test/test_random_expression.py b/test/test_random_expression.py
index f69a627..bed6114 100644
--- a/test/test_random_expression.py
+++ b/test/test_random_expression.py
@@ -77,9 +77,18 @@ class TestRandomExpression(unittest.TestCase):
 
 
     def test_only_form_calc_cond_calc(self):
-        form = "{a} + 2"
+        form = "{a*3} * {b}"
+        cond = ["{a + b} == 3"]
+        rdExp = RdExpression(form, cond)
 
-        pass
+        self.assertEqual(rdExp._letters, {'a', 'b'})
+        self.assertEqual(rdExp._2replaced, {'b', 'a*3', 'a + b'})
+
+        rdExp()
+        self.assertEqual(set(rdExp._gene_varia.keys()), {'a', 'b'}) 
+        self.assertEqual(set(rdExp._gene_2replaced.keys()), {'b', 'a*3', 'a + b'}) 
+
+        self.assertEqual((rdExp._gene_varia['a'] + rdExp._gene_varia['b']), 3)