This will get you close, the add button has been removed out of the table so you might want to consider this...
<script type="text/javascript">
$(document).ready(function() {
$("#add").click(function() {
$('#mytable tbody>tr:last').clone(true).insertAfter('#mytable tbody>tr:last');
return false;
});
});
</script>
HTML markup looks like this
<a id="add">+</a></td>
<table id="mytable" width="300" border="1" cellspacing="0" cellpadding="2">
<tbody>
<tr>
<td>Name</td>
</tr>
<tr class="person">
<td><input type="text" name="name" id="name" /></td>
</tr>
</tbody>
</table>
EDIT To empty a value of a textbox after insert..
$('#mytable tbody>tr:last').clone(true).insertAfter('#mytable tbody>tr:last');
$('#mytable tbody>tr:last #name').val('');
return false;
EDIT2 Couldn't help myself, to reset all dropdown lists in the inserted TR you can do this
$("#mytable tbody>tr:last").each(function() {this.reset();});
I will leave the rest to you!