求助，这个怎么了

VBA 帮助中有一段： ///////////////////////////////////////////////////////////////////////////////////////////////////

示例以下示例向幻灯片添加一个形状，并对该形状添加动画，然后在单击该形状三秒钟后开始动画。
Sub AddShapeSetTiming()
    Dim effDiamond As Effect
    Dim shpRectangle As Shape
  
    Set shpRectangle = ActivePresentation.Slides(1).Shapes _
        .AddShape(Type:=msoShapeRectangle, Left:=100, _
        Top:=100, Width:=50, Height:=50)     
        
        
    Set effDiamond = ActivePresentation.Slides(1).TimeLine.MainSequence _
        .AddEffect(Shape:=rect, effectId:=msoAnimEffectPathDiamond)
        
        
    With effDiamond.Timing
        .Duration = 5
        .TriggerShape = shpRectangle
        .TriggerType = msoAnimTriggerOnShapeClick
        .TriggerDelayTime = 3
    End With
End Sub

实现无误，我想进一步操作，改了三句就不能执行了：
Dim rect As Shape

Set rect = shpRectangle.Duplicate

Set effDiamond = ActivePresentation.Slides(1).TimeLine.MainSequence _
        .AddEffect(Shape:=rect, effectId:=msoAnimEffectPathDiamond)

请问：问题在哪里啊