diff --git a/examples/animals/AnimalsFre.gf b/examples/animals/AnimalsFre.gf
index 198c84ad7..7a8ec0c25 100644
--- a/examples/animals/AnimalsFre.gf
+++ b/examples/animals/AnimalsFre.gf
@@ -7,7 +7,7 @@ concrete AnimalsFre of Animals = QuestionsFre **
     Dog   = regN "chien" ;
     Cat   = regN "chat" ;
     Mouse = regGenN "souris" feminine ;
-    Lion  = regN "lion" ;
+    Lion  = mkN "lion" masculine ;
     Zebra = regGenN "zèbre" masculine ;
     Chase = dirV2 (regV "chasser") ;
     Eat   = dirV2 (regV "manger") ;
diff --git a/examples/animals/QuestionsI.gf b/examples/animals/QuestionsI.gf
index c35eeb796..ce0cb627a 100644
--- a/examples/animals/QuestionsI.gf
+++ b/examples/animals/QuestionsI.gf
@@ -1,4 +1,4 @@
--- to compile: echo "eb -file=QuestionsI.gfe" | gf $GF_LIB_PATH/present/LangEng.gfo
+-- to compile: echo "eb -file=QuestionsI.gfe" -probs=probs | gf $GF_LIB_PATH/present/LangEng.gfo
 -- or use directly gf <mkAnimals.gfs
 
 incomplete concrete QuestionsI of Questions = open Lang in {
@@ -10,17 +10,20 @@ incomplete concrete QuestionsI of Questions = open Lang in {
   lin 
     Who  love_V2 man_N           = (
 --- WARNING: ambiguous example who loves men
-UttQS (UseQCl (TTAnt TPres ASimul) PPos (QuestVP whoSg_IP (ComplSlash (SlashV2a love_V2) (DetCN (DetQuant IndefArt NumPl) (UseN man_N)))))
+UttQS (UseQCl (TTAnt TPres ASimul) PPos (QuestVP whoSg_IP (ComplSlash (SlashV2a love_V2) (DetCN (DetQuant IndefArt NumPl) (UseN man_N)))))  -- 2.122431752061382e-11
 )
  ;
     Whom man_N love_V2           = (
 --- WARNING: ambiguous example whom does the man love
-UttQS (UseQCl (TTAnt TPres ASimul) PPos (QuestSlash whoPl_IP (SlashVP (DetCN (DetQuant DefArt NumSg) (UseN man_N)) (SlashV2a love_V2))))
-  --- UttQS (UseQCl (TTAnt TPres ASimul) PPos (QuestSlash whoSg_IP (SlashVP (DetCN (DetQuant DefArt NumSg) (UseN man_N)) (SlashV2a love_V2))))
+UttQS (UseQCl (TTAnt TPres ASimul) PPos (QuestSlash whoPl_IP (SlashVP (DetCN (DetQuant DefArt NumSg) (UseN man_N)) (SlashV2a love_V2))))  -- 1.3265198450383634e-11
+  --- UttQS (UseQCl (TTAnt TPres ASimul) PPos (QuestSlash whoSg_IP (SlashVP (DetCN (DetQuant DefArt NumSg) (UseN man_N)) (SlashV2a love_V2))))  -- 1.3265198450383634e-11
 )
  ;
     Answer woman_N love_V2 man_N = (
---- WARNING: cannot parse example the woman lovess men; unknown words: lovess
+--- WARNING: ambiguous example the woman loves men
+UttS (UseCl (TTAnt TPres ASimul) PPos (PredVP (DetCN (DetQuant DefArt NumSg) (UseN woman_N)) (ComplSlash (SlashV2a love_V2) (DetCN (DetQuant IndefArt NumPl) (UseN man_N)))))  -- 1.1637456560533483e-14
+  --- UttNP (DetCN (DetQuant DefArt NumSg) (ApposCN (ApposCN (UseN woman_N) (DetCN (DetQuant IndefArt NumPl) (UseN love_N))) (DetCN (DetQuant IndefArt NumPl) (UseN man_N))))  -- 2.018579347059343e-20
+  --- UttNP (DetCN (DetQuant DefArt NumSg) (ApposCN (UseN woman_N) (DetCN (DetQuant IndefArt NumPl) (ApposCN (UseN love_N) (DetCN (DetQuant IndefArt NumPl) (UseN man_N))))))  -- 2.018579347059343e-20
 )
  ;
 
diff --git a/examples/animals/QuestionsI.gfe b/examples/animals/QuestionsI.gfe
index abb28742b..03c4ad071 100644
--- a/examples/animals/QuestionsI.gfe
+++ b/examples/animals/QuestionsI.gfe
@@ -1,4 +1,4 @@
--- to compile: echo "eb -file=QuestionsI.gfe" | gf $GF_LIB_PATH/present/LangEng.gfo
+-- to compile: echo "eb -file=QuestionsI.gfe" -probs=probs | gf $GF_LIB_PATH/present/LangEng.gfo
 -- or use directly gf <mkAnimals.gfs
 
 incomplete concrete QuestionsI of Questions = open Lang in {
diff --git a/lib/src/probs b/lib/src/probs
index bc647bfa0..b8e784ec1 100644
--- a/lib/src/probs
+++ b/lib/src/probs
@@ -28,3 +28,5 @@ TFut 0.1
 TCond 0.1
 PPos 0.7
 
+ApposCN 0.01
+
diff --git a/src/compiler/GF/Command/Commands.hs b/src/compiler/GF/Command/Commands.hs
index b56c19d72..1d3ccd833 100644
--- a/src/compiler/GF/Command/Commands.hs
+++ b/src/compiler/GF/Command/Commands.hs
@@ -255,7 +255,8 @@ allCommands cod env@(pgf, mos) = Map.fromList [
        let file = optFile opts
        mprobs <- optProbs opts pgf
        let conf = configureExBased pgf (optMorpho opts) mprobs (optLang opts)
-       file' <- parseExamplesInGrammar conf file
+       (file',ws) <- parseExamplesInGrammar conf file
+       if null ws then return () else putStrLn ("unknown words: " ++ unwords ws)
        return (fromString ("wrote " ++ file')),
      needsTypeCheck = False
      }),
diff --git a/src/compiler/GF/Compile/ExampleBased.hs b/src/compiler/GF/Compile/ExampleBased.hs
index 93116c4eb..983f38869 100644
--- a/src/compiler/GF/Compile/ExampleBased.hs
+++ b/src/compiler/GF/Compile/ExampleBased.hs
@@ -1,26 +1,31 @@
-module GF.Compile.ExampleBased (parseExamplesInGrammar,configureExBased) where
+module GF.Compile.ExampleBased (
+  parseExamplesInGrammar,
+  configureExBased
+  ) where
 
 import PGF
 import PGF.Probabilistic
 import PGF.Morphology
 
-parseExamplesInGrammar :: ExConfiguration -> FilePath -> IO FilePath
+import Data.List
+
+parseExamplesInGrammar :: ExConfiguration -> FilePath -> IO (FilePath,[String])
 parseExamplesInGrammar conf file = do
   src <- readFile file                             -- .gfe
   let file' = take (length file - 3) file ++ "gf"  -- .gf
-  convertFile conf src file'
-  return file'
+  ws <- convertFile conf src file'
+  return (file',ws)
 
-convertFile :: ExConfiguration -> String -> FilePath -> IO ()
+convertFile :: ExConfiguration -> String -> FilePath -> IO [String]
 convertFile conf src file = do
   writeFile file "" -- "-- created by example-based grammar writing in GF\n"
-  conv src
+  conv [] src
  where
-  conv s = do
+  conv ws s = do
     (cex,end) <- findExample s
-    if null end then return () else do
-      convEx cex
-      conv end
+    if null end then return (nub (sort ws)) else do
+      ws2 <- convEx cex
+      conv (ws2 ++ ws) end
   findExample s = case s of
     '%':'e':'x':cs -> return $ getExample cs
     c:cs -> appf [c] >> findExample cs
@@ -37,12 +42,18 @@ convertFile conf src file = do
     appn "("
     let typ = maybe (error "no valid cat") id $ readType cat
     let ts = rank $ parse pgf lang typ ex
-    case ts of
-      []   -> appv ("WARNING: cannot parse example " ++ ex ++ 
-                    missingWordMsg morpho (words ex))
+    ws <- case ts of
+      []   -> do
+        let ws = morphoMissing morpho (words ex)
+        appv ("WARNING: cannot parse example " ++ ex) 
+        case ws of
+          [] -> return ()
+          _  -> appv ("  missing words: " ++ unwords ws)
+        return ws 
       t:tt -> appv ("WARNING: ambiguous example " ++ ex) >>
-              appn t >> mapM_ (appn . ("  --- " ++)) tt 
+              appn t >> mapM_ (appn . ("  --- " ++)) tt >> return []
     appn ")"
+    return ws
   rank ts = case probs conf of
     Just probs -> [showExpr [] t ++ "  -- " ++ show p | (t,p) <- rankTreesByProbs probs ts]
     _ -> map (showExpr []) ts