diff --git a/src/Gyehoek/Scheme/Expand.hs b/src/Gyehoek/Scheme/Expand.hs
index 5f06f81..500f542 100644
--- a/src/Gyehoek/Scheme/Expand.hs
+++ b/src/Gyehoek/Scheme/Expand.hs
@@ -218,6 +218,31 @@ matches ps es = getAp . foldMap Ap $ alignWith f ps es
 
 
 
+trans_when :: Trans
+trans_when = MkTrans
+  { ellipsis = "..."
+  , keywords = []
+  , rules =
+    [ MkRule
+      (PatList
+        [ PatVar "when"
+        , PatVar "test"
+        , PatVar "body" ]
+        (Just [])
+        Nothing)
+      (TemList
+        [ El $ TemVar "if"
+        , El $ TemVar "test"
+        , El $ TemList
+          [ El $ TemVar "begin"
+          , Ellipsis $ TemVar "body"
+          ]
+          Nothing
+        ]
+        Nothing)
+    ]
+  }
+
 trans_and :: Trans
 trans_and = MkTrans
   { ellipsis = "..."
@@ -229,5 +254,27 @@ trans_and = MkTrans
           Nothing
           Nothing)
         (TemLit (LitBool True))
+    , MkRule
+        (PatList
+          [PatVar "and", PatVar "x"]
+          Nothing
+          Nothing)
+        (TemVar "x")
+    , MkRule
+        (PatList
+          [PatVar "and", PatVar "x", PatVar "y"]
+          (Just [])
+          Nothing)
+        (TemList
+          [ El (TemVar "if")
+          , El (TemVar "x")
+          , El (TemList
+              [ El (TemVar "and")
+              , Ellipsis (TemVar "y")
+              ]
+              Nothing)
+          , El . TemLit . LitBool $ False
+          ]
+          Nothing)
     ]
   }