diff --git a/supported.md b/supported.md
index 5e1c5a3..4dac6f2 100644
--- a/supported.md
+++ b/supported.md
@@ -102,7 +102,10 @@ List of supported MEI elements and attributes
 
 * `<dynam>`
   * `@endid`
+  * `@extender`
   * `@ho`
+  * `@lform`
+  * `@lwidth`
   * `@place`
   * __`@startid`__
   * `@vo`