Edit in JSFiddle

<script type="text/javascript" type="javascript" src="http://ajax.aspnetcdn.com/ajax/jquery.validate/1.9/jquery.validate.js"></script>
<form id="validate" action="validate.html" method="post" name="validate">

<label for="nome">Nome:</label>
<input type="text" name="nome" />

<label for="idade">Idade:</label>
<input type="text" name="idade" />

<label for="email">E-mail:</label>
<input type="text" name="email" />

<label for="pais">PaĆ­s:</label>

<select name="pais"> <option value="">Selecione</option> <option value="brasil">Brasil</option> <option value="canada">Inglaterra</option> </select><input type="submit" value="Validar" />

</form>