diff --git a/tests/test08.8pus b/tests/test08.8pus
index f253a43..15d633f 100644
--- a/tests/test08.8pus
+++ b/tests/test08.8pus
@@ -1 +1,7 @@
 (A -> B) -> ~B -> ~A
+intro f.
+intro b.
+intro a.
+apply b.
+apply f.
+assumption.