Imports System.Globalization, System.Threading
Public Class frmMainForm
 
....
 
    Private Sub mnuLanguageEnglish_Click(ByVal sender As System.Object, ByVal e _
      As System.EventArgs) Handles mnuLanguageEnglish.Click
        Me.mnuLanguageEnglish.Checked = Me.changeLanguage(1)
        Thread.CurrentThread.CurrentUICulture = New CultureInfo("en-GB")
    End Sub
 
...
End Class

Imports System.Globalization, System.Threading
Public Class frmMainForm
....
   Public Sub New()
        Thread.CurrentThread.CurrentUICulture = New CultureInfo("en-GB")
        ' Thread.CurrentThread.CurrentUICulture = New CultureInfo("de-DE") 
        ' wahlweise
 
        ' Dieser Aufruf ist für den Windows Form-Designer erforderlich.
        InitializeComponent()
 
        ' Fügen Sie Initialisierungen nach dem InitializeComponent()-Aufruf 
        ' hinzu.
 
    End Sub
...
End Class