asp語言中if判斷語句的求助

If a < 5 Then
  Response.Redirect("1.asp")
ElseIf a > 5 And a < 8 Then
  Response.Redirect("2.asp")
ElseIf a > 7 And a < 19 Then
  Response.Redirect("3.asp")
ElseIf a > 18 Then
  Response.Redirect("4.asp")
End If