function validate_form ( )
{
    valid = true;

    if ( document.classes.name.value == "" )
    {
        alert ( "Please Enter a Name" );
        valid = false;
    }

	if ( document.classes.age.value == "" )
    {
        alert ( "Please Select the age" );
        valid = false;
    }
	
	if ( document.classes.city.value == "" )
    {
        alert ( "Please Enter the city" );
        valid = false;
    }
	
	
	
	
	if ( document.classes.email.value == "" )
    {
        alert ( "Please your email address" );
        valid = false;
    }
	
	if ( document.classes.phone.value == "" )
    {
        alert ( "Please enter the phone number" );
        valid = false;
    }
    return valid;
}