diff --git a/pages/总复习2023t1.md b/pages/总复习2023t1.md
index 69750e3..b64d99e 100644
--- a/pages/总复习2023t1.md
+++ b/pages/总复习2023t1.md
@@ -2613,7 +2613,7 @@
 			  CLOCK: [2023-06-16 Fri 15:00:23]
 			  :END:
 				- Experiment, Sample Space and Random Event
-					-
+					- Definition: A random phenomenon is a situation in which we know what outcomes can happen, but not know which particular outcome did or will happen.
 			- LATER 学积分
 			  :LOGBOOK:
 			  CLOCK: [2023-06-03 Sat 17:05:07]--[2023-06-03 Sat 17:05:08] =>  00:00:01