I am a beginner in VBA and I am trying to obtain the script for a
task which, however simple it might look, I just cannot seem to get
it to work.
Concretely, I am trying to copy a range of cells in Worksheet1. The
uppermost left cell is B1 and the lowermost right cell is on column
D and the row is the lowest row of the used range.
Further, I want to paste this selection of 3 columns and n rows to
the bottom of the data that I already have in Worksheet2 (in my
trial columns A to C and again a number of rows which can vary)(I
want to keep the data existent in Worksheet2 and paste to its bottom
the data from Worksheet one)

I tried to do something like this:

Sub CopyAndPaste()

Dim x As Integer
Dim y As Integer
Dim z As Integer

x = Worksheets(1).UsedRange.Rows.Count
y = Worksheets(2).UsedRange.Rows.Count + 1
z = x + y

Sheets("Sheet1").Select
Range("B1:Dx").Select
Selection.Copy

Sheets("Sheet2").Select
Range("Ay:Cz").Select
ActiveSheet.Paste


End Sub

but I have no idea why it doesn't work, obviously there is a problem
with the language I used.