$('#form').submit(function(){
    validateForm1();
    validateForm(document.forms['dpart2']);
    validateForm(document.forms['dpart3']);
});

$('#form').submit(function(){
    return  validateForm1()
            && validateForm(document.forms['dpart2'])
            && validateForm(document.forms['dpart3']);
              }
});

$('#form').submit(function(){
    return (validateForm1() &&
            validateForm(document.forms['dpart2']) &&
            validateForm(document.forms['dpart3']))
});

$('#form').submit(function(){
    if (!validateForm1() || !validateForm(document.forms['dpart2']) || !validateForm(document.forms['dpart3'])) {
        return false;
    }
});

$("#myform").submit(function() {

    var ret = true;
    ret = validateForm1() && ret;
    ret = validateForm(document.forms['dpart2']) && ret
    ret = validateForm(document.forms['dpart3'])) && ret
    return ret;

});