求助，怎么用VBA改标注

Sub 尺寸标注单个更改()
Dim x As AcadObject
Dim pt3(2) As Double, pt1(2) As Double, pt2(2) As Double
pt1(0) = 0: pt1(1) = 0
pt2(0) = 0: pt2(1) = 500
pt3(0) = (pt1(0) + pt2(0)) / 2 + 120
pt3(1) = pt1(1): pt3(2) = 0
Set x = ThisDrawing.ModelSpace.AddDimAligned(pt1, pt2, pt3)
    x.Color = acYellow
    x.ArrowheadSize = 15
    x.TextHeight = 30
    x.TextSuffix = " 放外面"
    x.TextRotation = 4.712389
    x.VerticalTextPosition = acOutside
    x.TextOutsideAlign = True
End Sub