diff --git a/LanguageFeatures/nnbd/weak/type-normalization/equations_A01_t01.dart b/TypeSystem/type-normalization/weak/equations_A01_t01.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/equations_A01_t01.dart
rename to TypeSystem/type-normalization/weak/equations_A01_t01.dart
index e0e09a8ba7..64bff5b18e 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/equations_A01_t01.dart
+++ b/TypeSystem/type-normalization/weak/equations_A01_t01.dart
@@ -8,7 +8,6 @@
 ///   T?? == T?
 ///
 /// @description Checks that T?? == T?
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/equations_A02_t01.dart b/TypeSystem/type-normalization/weak/equations_A02_t01.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/equations_A02_t01.dart
rename to TypeSystem/type-normalization/weak/equations_A02_t01.dart
index ad327102d8..8781937ea1 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/equations_A02_t01.dart
+++ b/TypeSystem/type-normalization/weak/equations_A02_t01.dart
@@ -8,10 +8,10 @@
 ///   T?* == T?
 ///
 /// @description Checks that T?* == T?
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 import 'opted_in_lib.dart';
 import 'opted_out_lib.dart';
 
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/equations_A03_t01.dart b/TypeSystem/type-normalization/weak/equations_A03_t01.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/equations_A03_t01.dart
rename to TypeSystem/type-normalization/weak/equations_A03_t01.dart
index 266bee46b7..18d2c65250 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/equations_A03_t01.dart
+++ b/TypeSystem/type-normalization/weak/equations_A03_t01.dart
@@ -8,10 +8,10 @@
 ///   T*? == T?
 ///
 /// @description Checks that T*? == T?
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 import 'opted_in_lib.dart';
 import 'opted_out_lib.dart';
 
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/equations_A04_t01.dart b/TypeSystem/type-normalization/weak/equations_A04_t01.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/equations_A04_t01.dart
rename to TypeSystem/type-normalization/weak/equations_A04_t01.dart
index 858a8c8e6e..459249b655 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/equations_A04_t01.dart
+++ b/TypeSystem/type-normalization/weak/equations_A04_t01.dart
@@ -8,10 +8,10 @@
 ///   T** == T*
 ///
 /// @description Checks that T** == T*
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 import 'opted_out_lib.dart';
 
 class C extends LC2<String> implements LC<String> {}
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/equations_A05_t01.dart b/TypeSystem/type-normalization/weak/equations_A05_t01.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/equations_A05_t01.dart
rename to TypeSystem/type-normalization/weak/equations_A05_t01.dart
index dd24e293ea..d5c9c4a821 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/equations_A05_t01.dart
+++ b/TypeSystem/type-normalization/weak/equations_A05_t01.dart
@@ -8,10 +8,10 @@
 ///   Null? == Null
 ///
 /// @description Checks that Null? == Null
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 class A<X> {}
 class B<X> implements A<X> {}
 
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/equations_A06_t01.dart b/TypeSystem/type-normalization/weak/equations_A06_t01.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/equations_A06_t01.dart
rename to TypeSystem/type-normalization/weak/equations_A06_t01.dart
index fd3d4d1425..6a2dfb4aab 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/equations_A06_t01.dart
+++ b/TypeSystem/type-normalization/weak/equations_A06_t01.dart
@@ -8,10 +8,10 @@
 ///   Never? == Null
 ///
 /// @description Checks that Null? == Null
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 class A<X> {}
 class B<X> implements A<X> {}
 
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/equations_A07_t01.dart b/TypeSystem/type-normalization/weak/equations_A07_t01.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/equations_A07_t01.dart
rename to TypeSystem/type-normalization/weak/equations_A07_t01.dart
index ed9c7598c0..2f42165a40 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/equations_A07_t01.dart
+++ b/TypeSystem/type-normalization/weak/equations_A07_t01.dart
@@ -8,10 +8,10 @@
 ///   dynamic? == dynamic
 ///
 /// @description Checks that dynamic? == dynamic
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 class A<X> {}
 class B<X> implements A<X> {}
 
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/equations_A08_t01.dart b/TypeSystem/type-normalization/weak/equations_A08_t01.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/equations_A08_t01.dart
rename to TypeSystem/type-normalization/weak/equations_A08_t01.dart
index e451cc0a4f..e75df5edb0 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/equations_A08_t01.dart
+++ b/TypeSystem/type-normalization/weak/equations_A08_t01.dart
@@ -8,7 +8,6 @@
 ///   void? == void
 ///
 /// @description Checks that void? == void
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/equations_A09_t01.dart b/TypeSystem/type-normalization/weak/equations_A09_t01.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/equations_A09_t01.dart
rename to TypeSystem/type-normalization/weak/equations_A09_t01.dart
index 04a3dc41ef..4fca5b0669 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/equations_A09_t01.dart
+++ b/TypeSystem/type-normalization/weak/equations_A09_t01.dart
@@ -8,10 +8,10 @@
 ///   dynamic* == dynamic
 ///
 /// @description Checks that dynamic* == dynamic
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 import 'opted_out_lib.dart';
 
 class C extends LD implements LA<dynamic> {}
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/equations_A10_t01.dart b/TypeSystem/type-normalization/weak/equations_A10_t01.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/equations_A10_t01.dart
rename to TypeSystem/type-normalization/weak/equations_A10_t01.dart
index 716cc4692e..eb6e9781c9 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/equations_A10_t01.dart
+++ b/TypeSystem/type-normalization/weak/equations_A10_t01.dart
@@ -8,10 +8,10 @@
 ///   void* == void
 ///
 /// @description Checks that void* == void
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 import 'opted_out_lib.dart';
 
 class C extends LV implements LA<void> {}
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/equations_A11_t01.dart b/TypeSystem/type-normalization/weak/equations_A11_t01.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/equations_A11_t01.dart
rename to TypeSystem/type-normalization/weak/equations_A11_t01.dart
index 77ce2a65b8..c258ed2bef 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/equations_A11_t01.dart
+++ b/TypeSystem/type-normalization/weak/equations_A11_t01.dart
@@ -8,10 +8,10 @@
 ///   FutureOr<T> == T if Future<T> <: T
 ///
 /// @description Checks that if Future<T> <: T then FutureOr<T> == T
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 import 'dart:async';
 
 class A<X> {}
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/equations_A12_t01.dart b/TypeSystem/type-normalization/weak/equations_A12_t01.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/equations_A12_t01.dart
rename to TypeSystem/type-normalization/weak/equations_A12_t01.dart
index b9f8f4771b..7f299d93bc 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/equations_A12_t01.dart
+++ b/TypeSystem/type-normalization/weak/equations_A12_t01.dart
@@ -8,10 +8,10 @@
 ///   FutureOr<T> == Future<T> if T <: Future<T>
 ///
 /// @description Checks that if T <: Future<T> then FutureOr<T> == Future<T>
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 import 'dart:async';
 
 class A<X> {}
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/equations_A13_t01.dart b/TypeSystem/type-normalization/weak/equations_A13_t01.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/equations_A13_t01.dart
rename to TypeSystem/type-normalization/weak/equations_A13_t01.dart
index c75cae2267..a5f9b58cc1 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/equations_A13_t01.dart
+++ b/TypeSystem/type-normalization/weak/equations_A13_t01.dart
@@ -8,7 +8,6 @@
 ///   X extend Never == Never
 ///
 /// @description Checks that X extend Never == Never
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A02_t01.dart b/TypeSystem/type-normalization/weak/norm_A02_t01.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A02_t01.dart
rename to TypeSystem/type-normalization/weak/norm_A02_t01.dart
index 70fdc15763..5efc5de571 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A02_t01.dart
+++ b/TypeSystem/type-normalization/weak/norm_A02_t01.dart
@@ -14,10 +14,10 @@
 ///
 /// @description Checks that if NORM(T) is a top type then NORM(FutureOr<T>) =
 /// NORM(T)
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 import 'dart:async';
 
 class A<X> {}
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A02_t02.dart b/TypeSystem/type-normalization/weak/norm_A02_t02.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A02_t02.dart
rename to TypeSystem/type-normalization/weak/norm_A02_t02.dart
index a53680cad2..5af1f89fa3 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A02_t02.dart
+++ b/TypeSystem/type-normalization/weak/norm_A02_t02.dart
@@ -14,10 +14,10 @@
 ///
 /// @description Checks that if NORM(T) is Object then
 /// NORM(FutureOr<T>) = Object
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 import 'dart:async';
 
 class A<X> {}
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A02_t03.dart b/TypeSystem/type-normalization/weak/norm_A02_t03.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A02_t03.dart
rename to TypeSystem/type-normalization/weak/norm_A02_t03.dart
index 7d87bc4f45..d9959ddd85 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A02_t03.dart
+++ b/TypeSystem/type-normalization/weak/norm_A02_t03.dart
@@ -14,10 +14,10 @@
 ///
 /// @description Checks that if NORM(T) is Object* then
 /// NORM(FutureOr<T>) = Object*
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 import 'opted_out_lib.dart';
 
 class C extends LFO implements LAO {}
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A02_t04.dart b/TypeSystem/type-normalization/weak/norm_A02_t04.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A02_t04.dart
rename to TypeSystem/type-normalization/weak/norm_A02_t04.dart
index ddfe73f2d7..8999978421 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A02_t04.dart
+++ b/TypeSystem/type-normalization/weak/norm_A02_t04.dart
@@ -14,11 +14,11 @@
 ///
 /// @description Checks that if NORM(T) is Never then
 /// NORM(FutureOr<T>) = Future<Never>
-///
 /// @author sgrekhov@unipro.ru
 /// @issue 41632
 
 // Requirements=nnbd-weak
+
 import 'dart:async';
 
 class A<X> {}
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A02_t05.dart b/TypeSystem/type-normalization/weak/norm_A02_t05.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A02_t05.dart
rename to TypeSystem/type-normalization/weak/norm_A02_t05.dart
index 90aa5d6a9b..180305e446 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A02_t05.dart
+++ b/TypeSystem/type-normalization/weak/norm_A02_t05.dart
@@ -14,10 +14,10 @@
 ///
 /// @description Checks that if NORM(T) is Null then
 /// NORM(FutureOr<T>) = Future<Null>?
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 import 'dart:async';
 
 class A<X> {}
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A02_t07.dart b/TypeSystem/type-normalization/weak/norm_A02_t07.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A02_t07.dart
rename to TypeSystem/type-normalization/weak/norm_A02_t07.dart
index 45592581fd..e2d7838845 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A02_t07.dart
+++ b/TypeSystem/type-normalization/weak/norm_A02_t07.dart
@@ -15,10 +15,10 @@
 /// @description Checks that otherwise NORM(FutureOr<T>) = FutureOr<NORM(T)>.
 /// Test that NORM(FutureOr<T??>) == FutureOr<T?> and
 /// NORM(FutureOr<Never?>) == FutureOr<Null>
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 import 'dart:async';
 
 class T {}
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t01.dart b/TypeSystem/type-normalization/weak/norm_A03_t01.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t01.dart
rename to TypeSystem/type-normalization/weak/norm_A03_t01.dart
index 2f5753a465..33fe1c852b 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t01.dart
+++ b/TypeSystem/type-normalization/weak/norm_A03_t01.dart
@@ -16,7 +16,6 @@
 ///  else S?
 ///
 /// @description Checks that if NORM(T) is a top type then NORM(T?) = NORM(T)
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t02.dart b/TypeSystem/type-normalization/weak/norm_A03_t02.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t02.dart
rename to TypeSystem/type-normalization/weak/norm_A03_t02.dart
index fd866bb3bc..b082816f90 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t02.dart
+++ b/TypeSystem/type-normalization/weak/norm_A03_t02.dart
@@ -16,7 +16,6 @@
 ///  else S?
 ///
 /// @description Checks that if NORM(T) is Never then NORM(T?) = Null
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t03.dart b/TypeSystem/type-normalization/weak/norm_A03_t03.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t03.dart
rename to TypeSystem/type-normalization/weak/norm_A03_t03.dart
index 361309c3d6..dbd8a5a95e 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t03.dart
+++ b/TypeSystem/type-normalization/weak/norm_A03_t03.dart
@@ -16,7 +16,6 @@
 ///  else S?
 ///
 /// @description Checks that if NORM(T) is Never* then NORM(T?) = Null
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t04.dart b/TypeSystem/type-normalization/weak/norm_A03_t04.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t04.dart
rename to TypeSystem/type-normalization/weak/norm_A03_t04.dart
index 759bcf1636..67ad7f9985 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t04.dart
+++ b/TypeSystem/type-normalization/weak/norm_A03_t04.dart
@@ -16,10 +16,10 @@
 ///  else S?
 ///
 /// @description Checks that if NORM(T) is Null then NORM(T?) = Null
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 class A<X> {}
 class B1<X> implements A<X> {}
 class B2<X> implements A<X?> {}
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t05.dart b/TypeSystem/type-normalization/weak/norm_A03_t05.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t05.dart
rename to TypeSystem/type-normalization/weak/norm_A03_t05.dart
index f683e1e693..11431f77b7 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t05.dart
+++ b/TypeSystem/type-normalization/weak/norm_A03_t05.dart
@@ -17,11 +17,12 @@
 ///
 /// @description Checks that if NORM(T) is FutureOr<R> and R is nullable then
 /// NORM(T?) = FutureOr<R>
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 import 'dart:async';
+
 class A<X> {}
 class B1<X> implements A<X> {}
 class B2<X> implements A<FutureOr<X?>?> {}
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t07.dart b/TypeSystem/type-normalization/weak/norm_A03_t07.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t07.dart
rename to TypeSystem/type-normalization/weak/norm_A03_t07.dart
index fd2171af65..f44ece079e 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t07.dart
+++ b/TypeSystem/type-normalization/weak/norm_A03_t07.dart
@@ -17,10 +17,10 @@
 ///
 /// @description Checks that if NORM(T) is FutureOr<R>* and R is nullable then
 /// NORM(T?) = FutureOr<R>
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 import 'dart:async';
 import 'opted_in_lib.dart';
 import 'opted_out_lib.dart';
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t08.dart b/TypeSystem/type-normalization/weak/norm_A03_t08.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t08.dart
rename to TypeSystem/type-normalization/weak/norm_A03_t08.dart
index 7e81658fe5..acf672d403 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t08.dart
+++ b/TypeSystem/type-normalization/weak/norm_A03_t08.dart
@@ -16,10 +16,10 @@
 ///  else S?
 ///
 /// @description Checks that if NORM(T) is R? then NORM(T?) = R?
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 class T {}
 class A<X> {}
 class B<X> implements A<X?> {}
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t09.dart b/TypeSystem/type-normalization/weak/norm_A03_t09.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t09.dart
rename to TypeSystem/type-normalization/weak/norm_A03_t09.dart
index 8b68afd319..71116f2e7d 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t09.dart
+++ b/TypeSystem/type-normalization/weak/norm_A03_t09.dart
@@ -16,10 +16,10 @@
 ///  else S?
 ///
 /// @description Checks that if NORM(T) is R* then NORM(T?) = R?
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 import 'opted_in_lib.dart';
 import 'opted_out_lib.dart';
 
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t10.dart b/TypeSystem/type-normalization/weak/norm_A03_t10.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t10.dart
rename to TypeSystem/type-normalization/weak/norm_A03_t10.dart
index 71a5cef511..bf785e317a 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A03_t10.dart
+++ b/TypeSystem/type-normalization/weak/norm_A03_t10.dart
@@ -16,10 +16,10 @@
 ///  else S?
 ///
 /// @description Checks that if NORM(T) is S then NORM(T?) = S?
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 class T {}
 class A<X> {}
 class B<X> implements A<X?> {}
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A04_t01.dart b/TypeSystem/type-normalization/weak/norm_A04_t01.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A04_t01.dart
rename to TypeSystem/type-normalization/weak/norm_A04_t01.dart
index d6980d3ee4..95958fcb04 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A04_t01.dart
+++ b/TypeSystem/type-normalization/weak/norm_A04_t01.dart
@@ -12,10 +12,10 @@
 ///  else S*
 ///
 /// @description Checks that if NORM(T) is a top type then NORM(T*) = NORM(T)
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 import 'opted_in_lib.dart';
 import 'opted_out_lib.dart';
 
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A04_t02.dart b/TypeSystem/type-normalization/weak/norm_A04_t02.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A04_t02.dart
rename to TypeSystem/type-normalization/weak/norm_A04_t02.dart
index d4f3957d92..9d30aff3b1 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A04_t02.dart
+++ b/TypeSystem/type-normalization/weak/norm_A04_t02.dart
@@ -12,10 +12,10 @@
 ///  else S*
 ///
 /// @description Checks that if NORM(T) is Null then NORM(T*) = Null
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 import 'opted_in_lib.dart';
 import 'opted_out_lib.dart';
 
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A04_t03.dart b/TypeSystem/type-normalization/weak/norm_A04_t03.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A04_t03.dart
rename to TypeSystem/type-normalization/weak/norm_A04_t03.dart
index 3d3a4fd7c0..a76c1e895c 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A04_t03.dart
+++ b/TypeSystem/type-normalization/weak/norm_A04_t03.dart
@@ -12,10 +12,10 @@
 ///  else S*
 ///
 /// @description Checks that if NORM(T) is R? then NORM(T*) = R?
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 import 'opted_in_lib.dart';
 import 'opted_out_lib.dart';
 
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A04_t04.dart b/TypeSystem/type-normalization/weak/norm_A04_t04.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A04_t04.dart
rename to TypeSystem/type-normalization/weak/norm_A04_t04.dart
index a3373997cf..be8cec787c 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A04_t04.dart
+++ b/TypeSystem/type-normalization/weak/norm_A04_t04.dart
@@ -12,10 +12,10 @@
 ///  else S*
 ///
 /// @description Checks that if NORM(T) is R* then NORM(T*) = R*
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 import 'opted_out_lib.dart';
 
 class C extends LC2<String> implements LC<String> {}
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A05_t01.dart b/TypeSystem/type-normalization/weak/norm_A05_t01.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A05_t01.dart
rename to TypeSystem/type-normalization/weak/norm_A05_t01.dart
index c1c0707432..46511b6b81 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A05_t01.dart
+++ b/TypeSystem/type-normalization/weak/norm_A05_t01.dart
@@ -9,10 +9,10 @@
 ///  else X extends T
 ///
 /// @description Checks that if NORM(T) is Never then NORM(X extends T) = Never
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 class A<X> {}
 class B<X extends Never> implements A<X> {}
 
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A05_t02.dart b/TypeSystem/type-normalization/weak/norm_A05_t02.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A05_t02.dart
rename to TypeSystem/type-normalization/weak/norm_A05_t02.dart
index 0971cecef3..77ccd242a0 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A05_t02.dart
+++ b/TypeSystem/type-normalization/weak/norm_A05_t02.dart
@@ -9,10 +9,10 @@
 ///  else X extends T
 ///
 /// @description Checks that if NORM(T) is NORM(X extends T)
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 class T {}
 class T1 extends T {}
 class T2 extends T {}
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t01.dart b/TypeSystem/type-normalization/weak/norm_A06_t01.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t01.dart
rename to TypeSystem/type-normalization/weak/norm_A06_t01.dart
index 87d811723f..f7feee0f88 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t01.dart
+++ b/TypeSystem/type-normalization/weak/norm_A06_t01.dart
@@ -7,10 +7,10 @@
 ///
 /// @description Checks that NORM(C<T0, ..., Tn>) = C<R0, ..., Rn> where Ri is
 /// NORM(Ti). Test T?? == T?
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 class T {}
 class A<X> {}
 class B<X> implements A<C<X?>> {}
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t02.dart b/TypeSystem/type-normalization/weak/norm_A06_t02.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t02.dart
rename to TypeSystem/type-normalization/weak/norm_A06_t02.dart
index 9c51c4f7ce..2beeb1e6e7 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t02.dart
+++ b/TypeSystem/type-normalization/weak/norm_A06_t02.dart
@@ -7,10 +7,10 @@
 ///
 /// @description Checks that NORM(C<T0, ..., Tn>) = C<R0, ..., Rn> where Ri is
 /// NORM(Ti). Test T?* == T?
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 import 'opted_in_lib.dart';
 import 'opted_out_lib.dart';
 
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t03.dart b/TypeSystem/type-normalization/weak/norm_A06_t03.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t03.dart
rename to TypeSystem/type-normalization/weak/norm_A06_t03.dart
index 4d41588b1f..1f4a79d062 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t03.dart
+++ b/TypeSystem/type-normalization/weak/norm_A06_t03.dart
@@ -7,10 +7,10 @@
 ///
 /// @description Checks that NORM(C<T0, ..., Tn>) = C<R0, ..., Rn> where Ri is
 /// NORM(Ti). Test T*? == T?
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 import 'opted_in_lib.dart';
 import 'opted_out_lib.dart';
 
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t04.dart b/TypeSystem/type-normalization/weak/norm_A06_t04.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t04.dart
rename to TypeSystem/type-normalization/weak/norm_A06_t04.dart
index 30e7dcead9..e860eb4f0d 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t04.dart
+++ b/TypeSystem/type-normalization/weak/norm_A06_t04.dart
@@ -7,10 +7,10 @@
 ///
 /// @description Checks that NORM(C<T0, ..., Tn>) = C<R0, ..., Rn> where Ri is
 /// NORM(Ti). Test T** == T*
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 import 'opted_out_lib.dart';
 
 class C extends LCG2<String> implements LCG<String> {}
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t05.dart b/TypeSystem/type-normalization/weak/norm_A06_t05.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t05.dart
rename to TypeSystem/type-normalization/weak/norm_A06_t05.dart
index 0638d7bf26..f2447468a1 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t05.dart
+++ b/TypeSystem/type-normalization/weak/norm_A06_t05.dart
@@ -7,10 +7,10 @@
 ///
 /// @description Checks that NORM(C<T0, ..., Tn>) = C<R0, ..., Rn> where Ri is
 /// NORM(Ti). Test Null?, dynamic?, Never?
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 class A<X> {}
 class B<X> implements A<X> {}
 
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t06.dart b/TypeSystem/type-normalization/weak/norm_A06_t06.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t06.dart
rename to TypeSystem/type-normalization/weak/norm_A06_t06.dart
index 20bbda101d..f20cc10936 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t06.dart
+++ b/TypeSystem/type-normalization/weak/norm_A06_t06.dart
@@ -7,10 +7,10 @@
 ///
 /// @description Checks that NORM(C<T0, ..., Tn>) = C<R0, ..., Rn> where Ri is
 /// NORM(Ti). Test void?
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 class A<X> {}
 class B<X> implements A<C<X?>> {}
 
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t07.dart b/TypeSystem/type-normalization/weak/norm_A06_t07.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t07.dart
rename to TypeSystem/type-normalization/weak/norm_A06_t07.dart
index 3dc5877ebc..9a6604add9 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t07.dart
+++ b/TypeSystem/type-normalization/weak/norm_A06_t07.dart
@@ -7,10 +7,10 @@
 ///
 /// @description Checks that NORM(C<T0, ..., Tn>) = C<R0, ..., Rn> where Ri is
 /// NORM(Ti). Test dynamic*
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 import 'opted_in_lib.dart';
 import 'opted_out_lib.dart';
 
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t08.dart b/TypeSystem/type-normalization/weak/norm_A06_t08.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t08.dart
rename to TypeSystem/type-normalization/weak/norm_A06_t08.dart
index b014f97e7c..e3eea5f52b 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t08.dart
+++ b/TypeSystem/type-normalization/weak/norm_A06_t08.dart
@@ -7,10 +7,10 @@
 ///
 /// @description Checks that NORM(C<T0, ..., Tn>) = C<R0, ..., Rn> where Ri is
 /// NORM(Ti). Test void*
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 import 'opted_in_lib.dart';
 import 'opted_out_lib.dart';
 
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t09.dart b/TypeSystem/type-normalization/weak/norm_A06_t09.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t09.dart
rename to TypeSystem/type-normalization/weak/norm_A06_t09.dart
index 29788d76cf..5e3b5ce1e2 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t09.dart
+++ b/TypeSystem/type-normalization/weak/norm_A06_t09.dart
@@ -7,10 +7,10 @@
 ///
 /// @description Checks that NORM(C<T0, ..., Tn>) = C<R0, ..., Rn> where Ri is
 /// NORM(Ti). Test FutureOr<T> where Future<T> <: T
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 import 'dart:async';
 
 class A<X> {}
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t10.dart b/TypeSystem/type-normalization/weak/norm_A06_t10.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t10.dart
rename to TypeSystem/type-normalization/weak/norm_A06_t10.dart
index 10002fd60b..8a5a0b46fd 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t10.dart
+++ b/TypeSystem/type-normalization/weak/norm_A06_t10.dart
@@ -7,10 +7,10 @@
 ///
 /// @description Checks that NORM(C<T0, ..., Tn>) = C<R0, ..., Rn> where Ri is
 /// NORM(Ti). Test FutureOr<T> == Future<T> where T <: Future<T>
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 import 'dart:async';
 
 class A<X> {}
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t11.dart b/TypeSystem/type-normalization/weak/norm_A06_t11.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t11.dart
rename to TypeSystem/type-normalization/weak/norm_A06_t11.dart
index 1cec51b0b9..b1ba4c7f41 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A06_t11.dart
+++ b/TypeSystem/type-normalization/weak/norm_A06_t11.dart
@@ -7,10 +7,10 @@
 ///
 /// @description Checks that NORM(C<T0, ..., Tn>) = C<R0, ..., Rn> where Ri is
 /// NORM(Ti). Test X extend Never == Never
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 class A<X> {}
 class B<X extends Never> implements A<C<X>> {}
 class C<X> {}
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A07_t01.dart b/TypeSystem/type-normalization/weak/norm_A07_t01.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A07_t01.dart
rename to TypeSystem/type-normalization/weak/norm_A07_t01.dart
index 41f4e4b26e..b379c9732f 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A07_t01.dart
+++ b/TypeSystem/type-normalization/weak/norm_A07_t01.dart
@@ -10,10 +10,10 @@
 ///
 /// @description Checks that NORM(R Function<X extends B>(S)) =
 /// R1 Function<X extends B1>(S1).
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 class A<X> {}
 class B<X> implements A<X> {}
 
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/norm_A07_t02.dart b/TypeSystem/type-normalization/weak/norm_A07_t02.dart
similarity index 99%
rename from LanguageFeatures/nnbd/weak/type-normalization/norm_A07_t02.dart
rename to TypeSystem/type-normalization/weak/norm_A07_t02.dart
index 42807642b8..01b9128529 100644
--- a/LanguageFeatures/nnbd/weak/type-normalization/norm_A07_t02.dart
+++ b/TypeSystem/type-normalization/weak/norm_A07_t02.dart
@@ -10,10 +10,10 @@
 ///
 /// @description Checks that NORM(R Function<X extends B>(S)) =
 /// R1 Function<X extends B1>(S1).
-///
 /// @author sgrekhov@unipro.ru
 
 // Requirements=nnbd-weak
+
 class A<X> {}
 class B<X> implements A<X> {}
 
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/opted_in_lib.dart b/TypeSystem/type-normalization/weak/opted_in_lib.dart
similarity index 100%
rename from LanguageFeatures/nnbd/weak/type-normalization/opted_in_lib.dart
rename to TypeSystem/type-normalization/weak/opted_in_lib.dart
diff --git a/LanguageFeatures/nnbd/weak/type-normalization/opted_out_lib.dart b/TypeSystem/type-normalization/weak/opted_out_lib.dart
similarity index 100%
rename from LanguageFeatures/nnbd/weak/type-normalization/opted_out_lib.dart
rename to TypeSystem/type-normalization/weak/opted_out_lib.dart