function send() {
if (verifica())
document.forms[0].submit()}

function verifica(){
var re=/([^@]*)@([^@]*)\.(.*)/;

if(document.forms[0].n1.value=="") { alert("Introduceti numele"); document.forms[0].n1.focus(); return false; }
if(document.forms[0].n2.value=="") { alert("Introduceti numele companiei"); document.forms[0].n2.focus(); return false; }
if(document.forms[0].n3.value=="") { alert("Introduceti adresa companiei"); document.forms[0].n3.focus(); return false; }

if(document.forms[0].n4.value=="" || !re.exec(document.forms[0].n4.value)){
alert("Introduceti adresa de e-mail valida");
document.forms[0].n4.focus();
return false; 
}

return true; 
}