etc/isar-keywords.el

     "update_thy"
     "update_thy_only"
     "use"
     "use_thy"
     "use_thy_only"
+    "using"
     "welcome"
     "with"
     "{"
     "}"))
 

     "structure"
     "to"
     "transitions"
     "transrel"
     "uses"
-    "using"
     "where"))
 
 (defconst isar-keywords-control
   '("ProofGeneral\\.context_thy_only"
     "ProofGeneral\\.inform_file_processed"

   '("also"
     "let"
     "moreover"
     "note"
     "txt"
-    "txt_raw"))
+    "txt_raw"
+    "using"))
 
 (defconst isar-keywords-proof-asm
   '("assume"
     "case"
     "def"