VBA如何打开多个工作薄切换使用

Application.Workbooks.Open (PH1)
Application.Workbooks.Open (PH2)
Application.Workbooks.Open (PH3)
Application.Workbooks(PH2).Activate
一直提示Subscript out of range (Error 9)这个要怎么才能激活我想要的表然后复制黏贴。