diff --git a/app/test/test_next_essay.py b/app/test/test_next_essay.py
index 7a7ce18..75a06d4 100644
--- a/app/test/test_next_essay.py
+++ b/app/test/test_next_essay.py
@@ -41,7 +41,7 @@ def test_next():
         essay_content = elem.text
     
         # click Next
-        differ = 0
+        diff = 0
         for i in range(3):
             elem = driver.find_element_by_link_text('下一篇')
             elem.click()