function isEmailAddress (string) {
  var addressPattern = 
    /^\w+((-\w+)|(\.\w+))*\@[A-Za-z0-9]+((\.|-)[A-Za-z0-9]+)*\.[A-Za-z0-9]+$/;
  return addressPattern.test(string);
}



function ckeckform(form){
	
if(form.firstname.value.length==0 || form.firstname.value=="***Prosze wpisać Imię"){
form.firstname.value = "***Prosze wpisać Imię";
form.firstname.focus();
return  false;
}

if(form.surname.value.length==0 || form.surname.value=="***Prosze wpisać Nazwisko"){
form.surname.value = "***Prosze wpisać Nazwisko";
form.surname.focus();
return  false;
}

if(form.email.value.length==0 || form.email.value=="***Prosze wpisać email."){
form.email.value = "***Prosze wpisać email.";
form.email.focus();
return  false;}

if (!isEmailAddress(form.email.value)) {
form.email.value = "***Prosze wpisać poprawny email.";
form.email.focus();
return  false;}

return true;

}