diff --git a/core/object.rbs b/core/object.rbs
index 8feb2e3..8f81b7e 100644
--- a/core/object.rbs
+++ b/core/object.rbs
@@ -59,8 +59,8 @@ class Object < BasicObject
 
   def self.attr_accessor: (*Symbol names) -> void
 
-  def include: (Module, *Module mods) -> void
-  def self.include: (Module, *Module mods) -> void
+  def include: (*Module mods) -> void
+  def self.include: (*Module mods) -> void
 
   alias extend include
   alias self.extend self.include
diff --git a/test/object.rb b/test/object.rb
index b0c2281..0b6a68c 100644
--- a/test/object.rb
+++ b/test/object.rb
@@ -93,10 +93,10 @@ class A
   # @type const TestMod: Module
   module TestMod end
 
-  include TestMod
+  include
   include TestMod, TestMod, TestMod
 
-  extend TestMod
+  extend
   extend TestMod, TestMod, TestMod
 
   public
@@ -106,10 +106,10 @@ module TestMod end
   protected
 end
 
-Object.include TestMod
+Object.include
 Object.include TestMod, TestMod, TestMod
 
-Object.extend TestMod
+Object.extend
 Object.extend TestMod, TestMod, TestMod
 
 sprintf "%d\n", 123