diff --git a/R b/R
index 2dc1da8..bfe465e 100644
--- a/R
+++ b/R
@@ -7,37 +7,50 @@ BEGIN {
     _el=" el "; _defel="p"
 }
 
-function start(el) {
+function start(el, not_html) { # start an element
     el = (el ? el : _defel)
+    pre_el = (not_html ? "" : _el)
     split(el, el_a, " ")
     lvl[++i] = el_a[1]
-    return "$(<<" _end i lvl[i] _el el "\n"
+    return "$(<<" _end i lvl[i] pre_el el "\n"
 }
 
-function end() {
+function end() { # end an element
     return "\n" _end i lvl[i--] "\n)"
 }
 
-function wrap(par) {
+function wrap(par) { # wrap a non-delimited paragraph with <p>
     if (par !~ /^<.*>$/)
         return start() par end()
     else
         return par
 }
 
-/^@[^()]/ {
+/^@[^@()]/ { # html element
     $1 = start(substr($1, 2))
     sub(/\n?$/, end())
     print
     next
 }
 
-/^@\(/ {
+/^@@[^()]/ { # arbitrary command
+    $1 = start(substr($1, 3))
+    sub(/\n?$/, end())
+    print
+    next
+}
+
+/^@\(/ { # nested element begin
     print start(substr($1, 3))
     $1=""; $0=$0
 }
 
-/@\)$/ {
+/^@@\(/ { # nested arbitrary command begin
+    print start(substr($1, 4))
+    $1=""; $0=$0
+}
+
+/@@?\)$/ { # nested element end
     nf=$NF; NF--; $0=$0; print
     if ($0) {
         print wrap($0)