diff --git a/pages/总复习2023t1.md b/pages/总复习2023t1.md
index 903f1ef..74b2de9 100644
--- a/pages/总复习2023t1.md
+++ b/pages/总复习2023t1.md
@@ -982,6 +982,11 @@
 							- Process of minimizing differences between
 							  entities by identifying their common
 							  characteristics.
+						- Two constraints that may apply to a
+						  specialization/generalization:
+							- participation constraints
+							- disjoint constraints
+					-
 				- LATER designing ER diagram
 			- DONE Block 3
 			  collapsed:: true