function add_line() {

	aantal = prompt("hoeveel extra deelnemers wilt u toevoegen?");
	aantal = parseInt(aantal)+1

	for (i=1; i<aantal; i++) {

	var oLine = document.getElementById('namen');

	var oRow = document.createElement("tr");
	oLine.appendChild(oRow);

	var oCell = document.createElement("td");
	oRow.appendChild(oCell);
	var oLement = document.createElement("input");
	oLement.setAttribute("type", "text");
	oLement.setAttribute("name", "naam["+i+"]");
	oCell.appendChild(oLement);

	var oCell = document.createElement("td");
	oRow.appendChild(oCell);
	var oLement = document.createElement("input");
	oLement.setAttribute("type", "text");
	oLement.setAttribute("name", "voornaam["+i+"]");
	oCell.appendChild(oLement);

	var oCell = document.createElement("td");
	oRow.appendChild(oCell);
	var oLement = document.createElement("input");
	oLement.setAttribute("type", "radio");
	oLement.setAttribute("name", "gender["+i+"]");
	oLement.setAttribute("value", "Dhr");
	oCell.appendChild(oLement);
	oCell.appendChild(document.createTextNode("m"));

	var oLement = document.createElement("input");
	oLement.setAttribute("type", "radio");
	oLement.setAttribute("name", "gender["+i+"]");
	oLement.setAttribute("value", "Mw");
	oCell.appendChild(oLement);
	oCell.appendChild(document.createTextNode("v"));
	}

	document.getElementById('koppeling').style.display="none";
}