function addItem()
{
var last = document.getElementById('last_id').value;
last++;
document.getElementById('last_id').value = last;

var show = document.getElementById('users').innerHTML;
var ttt = '<p><nobr><INPUT class=text name="user_'+last+'">одно :<INPUT class=bd type=checkbox value=on name="user'+last+'_pl1">двухместный :<INPUT class=bd type=checkbox value=on name="user'+last+'_pl2"></nobr></p>';
document.getElementById('users').innerHTML = show + ttt;


}