对窗体编写如下事件过程: Private Sub Form. MouseDown(Button As Integer,Shift As Integer, _ x As Single, Y As Single) If Button=2 Then Print 'AAA' End If End Sub Private Sub Form. MouseUp (Button As Integer,Shift As Integer,_ x As Single,Y As Single) Print 'BBB' End Sub 程序运行后,如果单击鼠标右键,则输出结果为 ______。