diff --git a/src/dutch/AdjectiveDut.gf b/src/dutch/AdjectiveDut.gf
index 8a05ecb73..bd43bf9be 100644
--- a/src/dutch/AdjectiveDut.gf
+++ b/src/dutch/AdjectiveDut.gf
@@ -56,4 +56,6 @@ concrete AdjectiveDut of Adjective = CatDut ** open ResDut, Prelude in
       isPre = True
       } ;
 
+    AdvAP ap adv = {s = \\agr,af => ap.s ! agr ! af ++ adv.s ; isPre = False} ; -- KA: guessed
+
 }
diff --git a/src/estonian/AdjectiveEst.gf b/src/estonian/AdjectiveEst.gf
index 054452276..85f38ae32 100644
--- a/src/estonian/AdjectiveEst.gf
+++ b/src/estonian/AdjectiveEst.gf
@@ -61,4 +61,6 @@ concrete AdjectiveEst of Adjective = CatEst ** open ResEst, Prelude in {
       infl = a.infl
       } ;
 
+    AdvAP ap adv = {s = \\b,af => ap.s ! b ! af ++ adv.s ; infl = ap.infl} ; -- KA: guessed
+
 }