diff --git a/pages/总复习2023t1.md b/pages/总复习2023t1.md
index 65d0f84..b544d7b 100644
--- a/pages/总复习2023t1.md
+++ b/pages/总复习2023t1.md
@@ -1087,7 +1087,7 @@
 							- In the 2PL protocol, transactions acquire and release locks on database
 							  objects (e.g., tables, rows) in two distinct phases: the growing phase
 							  and the shrinking phase.
-						- DONE How timestamping can ensure serialisability. #flashcard
+						- LATER [#A] How timestamping can ensure serialisability. #flashcard
 						  id:: 64842000-07a7-4439-8ce6-7789e0a3358d
 							- By using transaction timestamps and enforcing the read and write
 							  validation checks, concurrency control mechanisms can ensure that