diff --git a/src/abstract/Extend.gf b/src/abstract/Extend.gf
index 475c41ab..ea9f9f3b 100644
--- a/src/abstract/Extend.gf
+++ b/src/abstract/Extend.gf
@@ -105,6 +105,10 @@ abstract Extend = Cat ** {
 
     NominalizeVPSlashNP : VPSlash -> NP -> NP ;
 
+-- counterpart to ProgrVP, for VPSlash
+
+    ProgrVPSlash : VPSlash -> VPSlash;
+
 -- existential for mathematics
 
     ExistsNP : NP -> Cl ;  -- there exists a number / there exist numbers
diff --git a/src/english/ExtendEng.gf b/src/english/ExtendEng.gf
index 3af375bf..c7e59914 100644
--- a/src/english/ExtendEng.gf
+++ b/src/english/ExtendEng.gf
@@ -222,6 +222,8 @@ concrete ExtendEng of Extend =
   lin
     PassVPSlash vps = passVPSlash (lin VPS vps) [] ;
     PassAgentVPSlash vps np = passVPSlash (lin VPS vps) ("by" ++ np.s ! NPAcc) ;
+    ProgrVPSlash vp = insertObjc (\\a => vp.ad ! a ++ vp.prp ++ vp.p ++ vp.s2 ! a)
+      (predAux auxBe ** {c2 = vp.c2; gapInMiddle = vp.gapInMiddle; missingAdv = vp.missingAdv});
 
    --- AR 7/3/2013
    ComplSlashPartLast vps np = case vps.gapInMiddle of {