diff --git a/lib/6to5/transformation/transformers/es6-let-scoping.js b/lib/6to5/transformation/transformers/es6-let-scoping.js
index f6d9010154..353dc578d1 100644
--- a/lib/6to5/transformation/transformers/es6-let-scoping.js
+++ b/lib/6to5/transformation/transformers/es6-let-scoping.js
@@ -265,11 +265,11 @@ LetScoping.prototype.checkFor = function () {
   traverse(this.block, function (node) {
     var replace;
 
-    if (t.isFunction(node) || t.isFor(node)) {
+    if (t.isFunction(node) || t.isLoop(node) || t.isSwitchStatement(node)) {
       return false;
     }
 
-    if (forParent && node && !node.label) {
+    if (node && !node.label) {
       if (t.isBreakStatement(node)) {
         has.hasBreak = true;
         replace = t.returnStatement(t.literal("break"));
diff --git a/lib/6to5/types/alias-keys.json b/lib/6to5/types/alias-keys.json
index b8920e3cd3..0dc76ee2b6 100644
--- a/lib/6to5/types/alias-keys.json
+++ b/lib/6to5/types/alias-keys.json
@@ -3,14 +3,14 @@
   "BreakStatement":      ["Statement"],
   "ContinueStatement":   ["Statement"],
   "DebuggerStatement":   ["Statement"],
-  "DoWhileStatement":    ["Statement"],
+  "DoWhileStatement":    ["Statement", "Loop", "With"],
   "IfStatement":         ["Statement"],
   "ReturnStatement":     ["Statement"],
   "SwitchStatement":     ["Statement"],
   "ThrowStatement":      ["Statement"],
   "TryStatement":        ["Statement"],
   "WhileStatement":      ["Statement"],
-  "WithStatement":       ["Statement"],
+  "WithStatement":       ["Statement", "Loop", "With"],
   "EmptyStatement":      ["Statement"],
   "LabeledStatement":    ["Statement"],
   "VariableDeclaration": ["Statement", "Declaration"],
@@ -35,9 +35,9 @@
   "ClassDeclaration": ["Statement", "Declaration", "Class"],
   "ClassExpression":  ["Class"],
 
-  "ForOfStatement": ["Statement", "For", "Scope"],
-  "ForInStatement": ["Statement", "For", "Scope"],
-  "ForStatement":   ["Statement", "For", "Scope"],
+  "ForOfStatement": ["Statement", "For", "Scope", "Loop"],
+  "ForInStatement": ["Statement", "For", "Scope", "Loop"],
+  "ForStatement":   ["Statement", "For", "Scope", "Loop"],
 
   "ObjectPattern": ["Pattern"],
   "ArrayPattern":  ["Pattern"],