diff --git a/dr_botzo/markov/lib.py b/dr_botzo/markov/lib.py
index 9198ef4..9e7243a 100644
--- a/dr_botzo/markov/lib.py
+++ b/dr_botzo/markov/lib.py
@@ -21,8 +21,9 @@ def generate_line(context, topics=None, min_words=15, max_words=30, sentence_bia
         if len(line) >= min_words:
             return line
         else:
-            if line[-1][-1] not in [',', '.', '!', '?', ':']:
-                line[-1] += random.choice(['?', '.', '!'])
+            if len(line) > 0:
+                if line[-1][-1] not in [',', '.', '!', '?', ':']:
+                    line[-1] += random.choice(['?', '.', '!'])
 
         tries += 1