diff --git a/MoganSTEMTutorial/math_mode_00.tm b/MoganSTEMTutorial/math_mode_00.tm
index 6815f8c..b131f02 100644
--- a/MoganSTEMTutorial/math_mode_00.tm
+++ b/MoganSTEMTutorial/math_mode_00.tm
@@ -6,53 +6,54 @@
   <screens|<\shown>
     <tit|\<#7B2C\>0\<#8BB2\>\<#FF1A\>\<#521D\>\<#8BC6\>\<#6570\>\<#5B66\>\<#6A21\>\<#5F0F\>>
 
-    <\big-table|<tabular|<tformat|<cwith|1|1|1|-1|cell-halign|c>|<cwith|2|-1|2|2|cell-halign|r>|<table|<row|<cell|\<#83DC\>\<#5355\>>|<cell|\<#5FEB\>\<#6377\>\<#952E\>>>|<row|<cell|<menu|Insert|Math|Inline
-    formula>>|<cell|<key|$>>>|<row|<cell|<menu|Insert|Math|Displayed
-    formula>>|<cell|<key|A-$>>>|<row|<cell|<menu|Insert|Math|Several
-    equations>>|<cell|<key|A-&>>>>>>>
-      \<#8FDB\>\<#5165\>\<#6570\>\<#5B66\>\<#6A21\>\<#5F0F\>
-    </big-table>
+    <\overlays|2|2>
+      <\big-table|<tabular|<tformat|<cwith|1|1|1|-1|cell-halign|c>|<cwith|2|-1|2|2|cell-halign|r>|<table|<row|<cell|\<#83DC\>\<#5355\>>|<cell|\<#5FEB\>\<#6377\>\<#952E\>>>|<row|<cell|<menu|Insert|Math|Inline
+      formula>>|<cell|<key|$>>>|<row|<cell|<menu|Insert|Math|Displayed
+      formula>>|<cell|<key|A-$>>>|<row|<cell|<menu|Insert|Math|Several
+      equations>>|<cell|<key|A-&>>>>>>>
+        \<#8FDB\>\<#5165\>\<#6570\>\<#5B66\>\<#6A21\>\<#5F0F\>
+      </big-table>
 
-    \;
+      \<#8FD9\>\<#662F\>\<#4E00\>\<#4E2A\>\<#6BB5\>\<#843D\>\<#FF0C\>\<#5B83\>\<#53EF\>\<#80FD\>\<#662F\>\<#4E00\>\<#884C\>\<#4E5F\>\<#53EF\>\<#80FD\>\<#662F\>\<#591A\>\<#884C\>\<#3002\>\<#8FD9\>\<#662F\>\<#4E00\>\<#4E2A\>\<#884C\>\<#5185\>\<#516C\>\<#5F0F\><math|\<alpha\>+\<beta\>>\<#FF0C\>\<#5B83\>\<#53EF\>\<#4EE5\>\<#88AB\>\<#5D4C\>\<#5165\>\<#5728\>\<#6BB5\>\<#843D\>\<#4E2D\>\<#3002\>
 
-    <\big-table|<tabular|<tformat|<cwith|2|2|3|3|cell-row-span|1>|<cwith|2|2|3|3|cell-col-span|2>|<cwith|1|-1|3|4|cell-halign|c>|<table|<row|<cell|\<#8F6E\>\<#6362\>>|<cell|\<#884C\>\<#5185\>\<rightarrow\>\<#5355\>\<#884C\>>|<cell|<key|A-S-up>>|<cell|<key|A-S-down>>>|<row|<cell|\<#5207\>\<#6362\>>|<cell|\<#5355\>\<#884C\><math|\<rightarrow\>>\<#591A\>\<#884C\>>|<cell|<key|C-&>>|<cell|>>>>>>
-      \<#8F6E\>\<#6362\>\<#548C\>\<#5207\>\<#6362\>
-    </big-table>
+      <\overlay-this|2>
+        <\big-table|<tabular|<tformat|<cwith|2|2|3|3|cell-row-span|1>|<cwith|2|2|3|3|cell-col-span|2>|<cwith|1|-1|3|4|cell-halign|c>|<table|<row|<cell|\<#7ED3\>\<#6784\>\<#53D8\>\<#5143\>\<#7684\>\<#8F6E\>\<#6362\>>|<cell|\<#884C\>\<#5185\>\<rightarrow\>\<#5355\>\<#884C\>>|<cell|<key|A-S-up>>|<cell|<key|A-S-down>>>|<row|<cell|\<#5207\>\<#6362\>>|<cell|\<#5355\>\<#884C\><math|\<rightarrow\>>\<#591A\>\<#884C\>>|<cell|<key|C-&>>|<cell|>>>>>>
+          \<#8F6E\>\<#6362\>\<#548C\>\<#5207\>\<#6362\>
+        </big-table>
 
-    <\equation*>
-      <around*|(|x+1|)><rsup|2>=x<rsup|2>+2*x+1
-    </equation*>
+        <equation*|<around*|(|x+1|)><rsup|3>=<around*|(|x<rsup|2>+2*x+1|)>*<around*|(|x+1|)>=x<rsup|3>+3*x<rsup|2>+3*x+1>
+      </overlay-this|>
+    </overlays>
 
     \<#672C\>\<#9875\>\<#5E7B\>\<#706F\>\<#7247\>\<#FF1A\>\<#70B9\>\<#51FB\><strong|<menu|Help|Planet>>\<#FF0C\>\<#70B9\>\<#51FB\><strong|\<#4ECE\>\<#96F6\>\<#5F00\>\<#59CB\>\<#5B66\>\<#58A8\>\<#5E72\>\<#7406\>\<#5DE5\>\<#5957\>\<#4EF6\>>\<#5373\>\<#53EF\>\<#627E\>\<#5230\>
 
     \;
 
     \;
+
+    \;
   </shown>>
 </body>
 
 <\initial>
   <\collection>
     <associate|info-flag|minimal>
+    <associate|page-height|auto>
     <associate|page-medium|beamer>
     <associate|page-screen-margin|false>
+    <associate|page-type|16:9>
+    <associate|page-width|auto>
   </collection>
 </initial>
 
 <\references>
   <\collection>
-    <associate|auto-1|<tuple|1|1|../../../Library/Application
-    Support/XmacsLabs/texts/scratch/no_name_6.tm>>
-    <associate|auto-2|<tuple|1|1|../../../Library/Application
-    Support/XmacsLabs/texts/scratch/no_name_6.tm>>
-    <associate|auto-3|<tuple|1|1|../../../Library/Application
-    Support/XmacsLabs/texts/scratch/no_name_6.tm>>
-    <associate|auto-4|<tuple|1|1|../../../Library/Application
-    Support/XmacsLabs/texts/scratch/no_name_6.tm>>
-    <associate|auto-5|<tuple|2|1|../../../Library/Application
-    Support/XmacsLabs/texts/scratch/no_name_6.tm>>
-    <associate|auto-6|<tuple|2|1|../../../Library/Application
-    Support/XmacsLabs/texts/scratch/no_name_6.tm>>
+    <associate|auto-1|<tuple|1|1>>
+    <associate|auto-2|<tuple|1|1>>
+    <associate|auto-3|<tuple|1|?>>
+    <associate|auto-4|<tuple|1|?>>
+    <associate|auto-5|<tuple|2|?>>
+    <associate|auto-6|<tuple|2|?>>
   </collection>
 </references>