diff --git a/assets/section_3.1_1686980736370_0.edn b/assets/section_3.1_1686980736370_0.edn
index e12e713..9297518 100644
--- a/assets/section_3.1_1686980736370_0.edn
+++ b/assets/section_3.1_1686980736370_0.edn
@@ -110,5 +110,17 @@
                                    :height 544.252}),
                           :page 22},
                :content {:text "Find the joint d.f. of X and Y ."},
-               :properties {:color "blue"}}],
- :extra {:page 27}}
+               :properties {:color "blue"}}
+              {:id #uuid "648d525e-f08f-4838-9103-0218fb369579",
+               :page 26,
+               :position {:bounding {:x1 45,
+                                     :y1 118.2490234375,
+                                     :x2 686,
+                                     :y2 470.2490234375,
+                                     :width 725.67,
+                                     :height 544.252},
+                          :rects (),
+                          :page 26},
+               :content {:text "[:span]", :image 1686983261351},
+               :properties {:color "yellow"}}],
+ :extra {:page 26}}
diff --git a/assets/section_3.1_1686980736370_0/26_648d525e-f08f-4838-9103-0218fb369579_1686983261351.png b/assets/section_3.1_1686980736370_0/26_648d525e-f08f-4838-9103-0218fb369579_1686983261351.png
new file mode 100644
index 0000000..7d70737
Binary files /dev/null and b/assets/section_3.1_1686980736370_0/26_648d525e-f08f-4838-9103-0218fb369579_1686983261351.png differ
diff --git a/pages/hls__section_3.1_1686980736370_0.md b/pages/hls__section_3.1_1686980736370_0.md
index a7b7d25..2ed9915 100644
--- a/pages/hls__section_3.1_1686980736370_0.md
+++ b/pages/hls__section_3.1_1686980736370_0.md
@@ -61,4 +61,11 @@ file-path:: ../assets/section_3.1_1686980736370_0.pdf
   ls-type:: annotation
   hl-page:: 22
   hl-color:: blue
-  id:: 648d5223-4e70-4b61-bb3c-89bad7b2d755
\ No newline at end of file
+  id:: 648d5223-4e70-4b61-bb3c-89bad7b2d755
+- [:span]
+  ls-type:: annotation
+  hl-page:: 26
+  hl-color:: yellow
+  id:: 648d525e-f08f-4838-9103-0218fb369579
+  hl-type:: area
+  hl-stamp:: 1686983261351
\ No newline at end of file
diff --git a/pages/总复习2023t1.md b/pages/总复习2023t1.md
index b375d58..ca835a6 100644
--- a/pages/总复习2023t1.md
+++ b/pages/总复习2023t1.md
@@ -2881,6 +2881,7 @@
 								  collapsed:: true
 									- ((648d4dd7-6ecc-479d-bd1e-0280c9bb7155))
 						- Discrete random vectors
+						  collapsed:: true
 							- JPF : ((648d4f01-6942-43ea-b5a1-159b99d49d7a))
 							- Marginal p.f. : ((648d4f45-89ee-420b-9b93-13076e232dff))
 							  collapsed:: true
@@ -2888,6 +2889,9 @@
 							- d.f. of random vector, example:
 								- ((648d5223-4e70-4b61-bb3c-89bad7b2d755))
 							-
+						- Continuous random vector
+							-
+							- ((648d525e-f08f-4838-9103-0218fb369579))
 			- LATER 学积分
 			  :LOGBOOK:
 			  CLOCK: [2023-06-03 Sat 17:05:07]--[2023-06-03 Sat 17:05:08] =>  00:00:01