how to add empty row PlaceHolder

[mohamed]

if (newgene == "0")
       {
           MainPlaceHolder.Controls.Add(holder);
       }
       else
       {
           MainPlaceHolder.Controls.Add(new LiteralControl("<br>"));
       }

See The Image ,
i want to space between the dropdown .
Thanks Advance,
Mohamed.

[mohamed]

Spacing problem is corrected

MainPlaceHolder.Controls.Add(new LiteralControl("<br><br><br><br>"));

PlaceHolder holder = new PlaceHolder();

CheckBox autoLabel = new CheckBox();
autoLabel.id= id.ToString() + ": ";
holder.Controls.Add(autoLabel);

RadComboBox autoTextBox = new RadComboBox();
autoTextBox.ID = "TextBox" + id.ToString();
holder.Controls.Add(autoTextBox);

mainPlaceHolder.Controls.Add(holder);

How i get the both Checkbox id , RadComboBox id ,
In the mainPlaceHolder

Regards,
Mohamed.