关于您在做什么错，我建议您使用

As to what are you doing wrong, I suggest you use

Sub Concat()
    Sheets("Sheet1").Select
    Dim lRow As Long, i As Long
    Dim rng As Range
    Set rng = Range("A" & Rows.Count).End(xlUp)
    Debug.Print rng.Address(External:=True)
    lRow = rng.Row
    For i = 2 To lRow
        ActiveWorkbook.Sheets("Sheet2").Cells(i, 1) = Cells(i, 1) & Cells(i, 2)
    Next i
End Sub

正在进行。我完全尝试了您使用的工具，并且对我有用（Excel 2010）。

to see what is going on. I tried exactly what you used and it worked for me (Excel 2010).

指定变量lRow不取任何值的含义将有所帮助。

Specifying what does "variable lRow is not taking any value" mean would help.

您也可以尝试或者

Sub Concat2()
    Sheets("Sheet1").Select
    Dim lRow As Long, i As Long
    Dim rng As Range
    Set rng = Range("A2").End(xlDown)
    Debug.Print rng.Address(External:=True)
    lRow = rng.Row
    For i = 2 To lRow
        ActiveWorkbook.Sheets("Sheet2").Cells(i, 1) = Cells(i, 1) & Cells(i, 2)
    Next i
End Sub

如果您在源列A的中间没有空白单元格，则结果相同。

which should give the same result if yo do not have blank cells in the middle of the source column A.