diff --git a/SICP/code06.tm b/SICP/code06.tm
new file mode 100644
index 0000000..0a68323
--- /dev/null
+++ b/SICP/code06.tm
@@ -0,0 +1,268 @@
+<TeXmacs|2.1.2>
+
+<style|<tuple|generic|no-page-numbers|british|reduced-margins>>
+
+<\body>
+  <section*|\<#7ED8\>\<#56FE\>>
+
+  <\session|scheme|default>
+    <\folded-io|Scheme] >
+      (define (plot l) (stree-\<gtr\>tree l))
+    <|folded-io>
+      plot
+    </folded-io>
+
+    <\folded-io|Scheme] >
+      (plot `(frac 1 2))
+    <|folded-io>
+      <text|<frac|1|2>>
+    </folded-io>
+
+    <\folded-io|Scheme] >
+      (plot `(point 0 0))
+    <|folded-io>
+      <text|<point|0|0>>
+    </folded-io>
+
+    <\folded-io|Scheme] >
+      (plot `(graphics (point -5 -5) (point 5 5))) ; quasiquote `
+    <|folded-io>
+      <text|<graphics|<point|-5|-5>|<point|5|5>>>
+    </folded-io>
+
+    <\folded-io|Scheme] >
+      (plot `(graphics (point ,(+ 1 2) ,(+ 1 3)) (point 0 0)))
+    <|folded-io>
+      <text|<with|gr-grid|<tuple|empty>|gr-grid-old|<tuple|cartesian|<point|0|0>|1>|gr-edit-grid-aspect|<tuple|<tuple|axes|none>|<tuple|1|none>|<tuple|10|none>>|gr-edit-grid|<tuple|empty>|gr-edit-grid-old|<tuple|cartesian|<point|0|0>|1>|<graphics|<point|3|4>|<point|0|0>>>>
+    </folded-io>
+
+    <\folded-io|Scheme] >
+      (plot `(graphics (point 0 0) (point 1 1) (line (point 0 0) (point 1
+      1)))))
+    <|folded-io>
+      <text|<graphics|<point|0|0>|<point|1|1>|<line|<point|0|0>|<point|1|1>>>>
+    </folded-io>
+
+    <\unfolded-io|Scheme] >
+      (plot `(cline (point 0 0) (point 3 0) (point 0 4)))
+    <|unfolded-io>
+      <text|<cline|<point|0|0>|<point|3|0>|<point|0|4>>>
+    </unfolded-io>
+
+    <\unfolded-io|Scheme] >
+      (kbd-map ("d i a n var" (insert (utf8-\<gtr\>cork "\<#70B9\>"))))
+    <|unfolded-io>
+      ("d i a n tab")
+    </unfolded-io>
+
+    <\unfolded-io|Scheme] >
+      (kbd-map ("h t var" (insert (utf8-\<gtr\>cork "\<#7ED8\>\<#56FE\>"))))
+    <|unfolded-io>
+      ("h t tab")
+    </unfolded-io>
+
+    <\unfolded-io|Scheme] >
+      (kbd-map ("t u var" (insert (utf8-\<gtr\>cork "\<#56FE\>"))))
+    <|unfolded-io>
+      ("t u tab")
+    </unfolded-io>
+
+    <\unfolded-io|Scheme] >
+      (kbd-map ("s j x var" (insert (utf8-\<gtr\>cork
+      "\<#4E09\>\<#89D2\>\<#5F62\>"))))
+    <|unfolded-io>
+      ("s j x tab")
+    </unfolded-io>
+
+    <\unfolded-io|Scheme] >
+      (kbd-map ("z s j x var" (insert (utf8-\<gtr\>cork
+      "\<#6B63\>\<#4E09\>\<#89D2\>\<#5F62\>"))))
+    <|unfolded-io>
+      ("z s j x tab")
+    </unfolded-io>
+
+    <\unfolded-io|Scheme] >
+      (define (\<#7ED8\>\<#56FE\> l) (stree-\<gtr\>tree l))
+    <|unfolded-io>
+      \<#7ED8\>\<#56FE\>
+    </unfolded-io>
+
+    <\unfolded-io|Scheme] >
+      (define (\<#70B9\> x y) `(point ,x ,y))
+    <|unfolded-io>
+      \<#70B9\>
+    </unfolded-io>
+
+    <\folded-io|Scheme] >
+      (define (\<#56FE\> . objects)
+
+      \ \ (cond ((nlist? objects) '(graphics "" ""))
+
+      \ \ \ \ \ \ \ \ ((== objects '()) '(graphics "" ""))
+
+      \ \ \ \ \ \ \ \ (else `(graphics "" ,@objects))))
+    <|folded-io>
+      \<#56FE\>
+    </folded-io>
+
+    <\folded-io|Scheme] >
+      (\<#7ED8\>\<#56FE\> (\<#56FE\> (\<#70B9\> 1 1) (\<#70B9\> 2 2)))
+    <|folded-io>
+      <text|<with|gr-grid|<tuple|cartesian|<point|0|0>|1>|gr-grid-old|<tuple|cartesian|<point|0|0>|1>|gr-edit-grid-aspect|<tuple|<tuple|axes|none>|<tuple|1|none>|<tuple|10|none>>|gr-edit-grid|<tuple|cartesian|<point|0|0>|1>|gr-edit-grid-old|<tuple|cartesian|<point|0|0>|1>|gr-frame|<tuple|scale|3cm|<tuple|0.5gw|0.5gh>>|magnify|3.0|<graphics||<point|1|1>|<point|2|2>>>>
+    </folded-io>
+
+    <\unfolded-io|Scheme] >
+      (define (triangle x y z)
+
+      \ \ `(cline ,x ,y ,z))
+    <|unfolded-io>
+      \<#4E09\>\<#89D2\>\<#5F62\>
+    </unfolded-io>
+
+    <\input|Scheme] >
+      (define (\<#4E09\>\<#89D2\>\<#5F62\> x y z) (triangle x y z))
+    </input>
+
+    <\unfolded-io|Scheme] >
+      (\<#7ED8\>\<#56FE\> (\<#4E09\>\<#89D2\>\<#5F62\> (\<#70B9\> 0 0 )
+      (\<#70B9\> 0 3) (\<#70B9\> 4 0)))
+    <|unfolded-io>
+      <text|<cline|<point|0|0>|<point|0|3>|<point|4|0>>>
+    </unfolded-io>
+
+    <\unfolded-io|Scheme] >
+      (car (cdr (cdr (\<#70B9\> 1 2)))) ; third
+    <|unfolded-io>
+      2
+    </unfolded-io>
+
+    <\unfolded-io|Scheme] >
+      (car (cdr (\<#70B9\> 1 2))) ; second
+    <|unfolded-io>
+      1
+    </unfolded-io>
+
+    <\unfolded-io|Scheme] >
+      (list-ref (list 1 2 3 4 5) 1)
+    <|unfolded-io>
+      2
+    </unfolded-io>
+
+    <\unfolded-io|Scheme] >
+      (define (\<#6B63\>\<#4E09\>\<#89D2\>\<#5F62\> A \<#8FB9\>\<#957F\>)
+
+      \ \ (\<#4E09\>\<#89D2\>\<#5F62\>
+
+      \ \ \ \ \ \ \ A
+
+      \ \ \ \ \ \ \ (\<#70B9\> (+ \<#8FB9\>\<#957F\> (second A)))
+
+      \ \ \ \ \ \ \ \ \ \ \ (third A))
+
+      \ \ \ \ \ \ \ (\<#70B9\> (+ (* 0.5 \<#8FB9\>\<#957F\>)
+
+      \ \ \ \ \ \ \ \ \ \ \ \ \ \ (second A))
+
+      \ \ \ \ \ \ \ \ \ \ \ (+ (third A) (* (sqrt 0.75)
+      \<#8FB9\>\<#957F\>))))))
+    <|unfolded-io>
+      \<#6B63\>\<#4E09\>\<#89D2\>\<#5F62\>
+    </unfolded-io>
+
+    <\unfolded-io|Scheme] >
+      (\<#7ED8\>\<#56FE\> (\<#6B63\>\<#4E09\>\<#89D2\>\<#5F62\> (\<#70B9\> 0
+      0) 3))
+    <|unfolded-io>
+      <errput|(symbol "ç\\x82;¹"): not enough arguments: ((lambda (x y) ...)
+      3)>
+    </unfolded-io>
+
+    <\unfolded-io|Scheme] >
+      (define (point x y) `(point ,x ,y))
+    <|unfolded-io>
+      point
+    </unfolded-io>
+
+    <\unfolded-io|Scheme] >
+      (point 1 2) =\<gtr\> (point "1" "2")
+    <|unfolded-io>
+      (point 1 2)
+    </unfolded-io>
+
+    <\unfolded-io|Scheme] >
+      (number? 1)
+    <|unfolded-io>
+      #t
+    </unfolded-io>
+
+    <\unfolded-io|Scheme] >
+      (number-\<gtr\>string 1)
+    <|unfolded-io>
+      (number-\<gtr\>string 1)
+    </unfolded-io>
+
+    <\unfolded-io|Scheme] >
+      \;
+    <|unfolded-io>
+      x-\<gtr\>string
+    </unfolded-io>
+
+    <\unfolded-io|Scheme] >
+      (define (draw x)
+
+      \ \ (define (x-\<gtr\>string x)
+
+      \ \ \ \ \ \ (if (number? x)
+
+      \ \ \ \ \ \ \ \ (number-\<gtr\>string x)
+
+      \ \ \ \ \ \ \ \ x))
+
+      \ \ (define (draw-inner x)
+
+      \ \ \ \ (if (eq? () x) ()
+
+      \ \ \ \ \ \ (cons (x-\<gtr\>string (car x))
+
+      \ \ \ \ \ \ \ \ \ \ \ \ (draw-inner (cdr x)))))
+
+      \ \ (stree-\<gtr\>tree (draw-inner x)))
+    <|unfolded-io>
+      draw
+    </unfolded-io>
+
+    <\unfolded-io|Scheme] >
+      (draw `(point 1 1))
+    <|unfolded-io>
+      <text|<point|1|1>>
+    </unfolded-io>
+
+    <\input|Scheme] >
+      \;
+    </input>
+  </session>
+</body>
+
+<\initial>
+  <\collection>
+    <associate|page-screen-margin|true>
+    <associate|preamble|false>
+    <associate|src-style|scheme>
+  </collection>
+</initial>
+
+<\references>
+  <\collection>
+    <associate|auto-1|<tuple|?|?>>
+  </collection>
+</references>
+
+<\auxiliary>
+  <\collection>
+    <\associate|toc>
+      <vspace*|1fn><with|font-series|<quote|bold>|math-font-series|<quote|bold>|\<#7ED8\>\<#56FE\>>
+      <datoms|<macro|x|<repeat|<arg|x>|<with|font-series|medium|<with|font-size|1|<space|0.2fn>.<space|0.2fn>>>>>|<htab|5mm>>
+      <no-break><pageref|auto-1><vspace|0.5fn>
+    </associate>
+  </collection>
+</auxiliary>
\ No newline at end of file
diff --git a/SICP/index.tm b/SICP/index.tm
index 61c33c5..572c36b 100644
--- a/SICP/index.tm
+++ b/SICP/index.tm
@@ -24,6 +24,10 @@
       <item>\<#76EE\>\<#6807\>\<#90AE\>\<#7BB1\>\<#FF1A\>shenda AT ustc.edu
     </itemize>
 
+    <item>\<#7B2C\>6\<#8BFE\>\<#FF1A\>\<#7B97\>\<#6CD5\>\<#7684\>\<#65F6\>\<#7A7A\>\<#590D\>\<#6742\>\<#5EA6\>\<#FF08\>\<#4E60\>\<#9898\>\<#8BFE\>\<#FF09\>
+
+    \<#4EE3\>\<#7801\>\<#FF1A\><hlink|\<#4EE3\>\<#7801\>\<#6E05\>\<#5355\>06|code06.tm>
+
     <item>\<#7B2C\>5\<#8BFE\>\<#FF1A\>\<#7B97\>\<#6CD5\>\<#7684\>\<#65F6\>\<#7A7A\>\<#590D\>\<#6742\>\<#5EA6\>
 
     \<#8BB2\>\<#4E49\>\<#FF1A\><hlink|\<#4EA4\>\<#4E92\>\<#5F0F\>\<#8BB2\>\<#4E49\>05|https://gitee.com/XmacsLabs/interactive-sicp/raw/main/course05.tm>