PIVOT TABLE ERROR Incorrect syntax near ' + VF '.

Dim strSQL2 As String = "SELECT [FeesType] FROM FeeMaster WHERE Class='" & cboClass.Text & "'"
        Dim DaAp2 As New SqlDataAdapter(strSQL2, con)
        Dim Dset2 As New DataTable
        DaAp27.Fill(Dset2)
        Dim VF
        For i = 0 To Dset2.Rows.Count - 1
            VF = Dset2.Rows(i).Item("FeesType")
        Next

        Dim strSQL1 As String
        strSQL1 = "SELECT * FROM (SELECT SA.Regno, SA.Sname, SA.Class, SA.Section , FT.FeeType," & _
            " FT.Amount_Paid  FROM Fees_Transaction as FT INNER JOIN stdAdmission as SA ON FT.Regno=SA.Regno) FeeMaster" & _
            " PIVOT (Sum(Amount_Paid) for FeeType in ( ' + VF ' + ))as PVT where Class='" & cboClass.Text & "'"
        Dim DaAp1 As New SqlDataAdapter(strSQL1, con)
        Dim DSet1 As New DataTable
        DaAp1.Fill(DSet1)
        DGV1.DataSource = DSet1