Sub test()
Application.ScreenUpdating = False
For n = Range("B" & Rows.Count).End(xlUp).Row To 1 Step -1
If Range("A" & n) = "" Then
For m = 2 To 4
Cells(n - 1, m) = Cells(n - 1, m) & " " & Cells(n, m)
Next
Rows(n).Delete
End If
Next
Application.ScreenUpdating = True
End Sub