diff --git a/ps-grammar/rsm/rsm.jsgf b/ps-grammar/rsm/rsm.jsgf
index 52c6c92dd64bdb929ee34ad5fac1fff97d4d6459..4a4d2a3acccef145baf95f9983ede3433cb3f9c0 100644
--- a/ps-grammar/rsm/rsm.jsgf
+++ b/ps-grammar/rsm/rsm.jsgf
@@ -2,7 +2,7 @@
 grammar A4_rsm;
 public <rsm> = [the] <furniture> is ( <IN_FRONT_OF> | <BEHIND> | <RIGHT_OF> | <LEFT_OF> ) of the <furniture>;
 
-<furniture> = ( ( sofa | couch ) | chair | cupboard | shelf | table ) ;
+<furniture> = ( ( sofa | couch ) | (armchair) | chair | cupboard | shelf | table ) ;
 <IN_FRONT_OF> = ( before | front );
 <BEHIND> = ( behind | after );
 <LEFT_OF> = ( left );