diff --git a/src/tfscript/verify.py b/src/tfscript/verify.py
index 84de8ee..973c8ff 100644
--- a/src/tfscript/verify.py
+++ b/src/tfscript/verify.py
@@ -183,6 +183,9 @@ def removeRelaventFields(key, data, bindType):
                 errMsgs.append('impulse requires `command` argument')
             else:
                 content.pop("command")
+        else:
+            if not isinstance(content, str) and not isinstance(content, list):
+                errMsgs.append(f'impulse must be a single string or list')
 
     elif bindType == "toggle":
         if isinstance(content, dict):
@@ -227,10 +230,10 @@ def removeRelaventFields(key, data, bindType):
             if not validKey(condition):
                 errMsgs.append(f'Invalid condition to toggle "{condition}"')
 
-        if "cancel both" in content:
-            cancelBoth = content["cancel both"]
-            if not isinstance(cancelBoth, bool):
-                errMsgs.append(f'"cancel both" field in "{key}" makes no sense: "{cancelBoth}"')
+        if "cancel" in content:
+            canType = content["cancel"]
+            if canType not in ["released", "both"]:
+                errMsgs.append(f'"cancel" must be either "released" or "both", not {canType}')
 
     elif bindType == "repeat":
         unit = "s"