Calling a WPF User Control from Windows form

I keep getting this error :

Error3 The type name 'IComponentConnector' could not be found in the namespace 'System.Windows.Markup'. This type has been forwarded to assembly 'System.Xaml, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' Consider adding a reference to that assembly.C:\Users\E574129\Documents\Visual Studio 2010\Projects\Angel\Angel\obj\x86\Debug\Angel2.g.cs4194 Angel

Error1 The type 'System.Windows.Markup.IQueryAmbient' is defined in an assembly that is not referenced. You must add a reference to assembly 'System.Xaml, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'.C:\Users\E574129\Documents\Visual Studio 2010\Projects\Angel\Angel\Angel2.xaml.cs2226 Angel

and I cant found  System.Windows.Markup.IQueryAmbient