HTML Form Validation

Hello,
I have an HTML form with some javascript error checking that looks something like this:

<script type=‘text/javascript’>
function formValidator(){
var firstname = document.getElementById(‘firstname’);
var addr = document.getElementById(‘addr’);

// Check each input in the order that it appears in the form!
if(isAlphabet(firstname, "Please enter only letters for your name")){
    if(isAlphanumeric(addr, "Numbers and Letters Only for Address")){
        
    }
}
    
return false;    

}

function isAlphabet(elem, helperMsg){
var alphaExp = /^[a-zA-Z]+$/;
if(elem.value.match(alphaExp)){
return true;
}else{
alert(helperMsg);
elem.focus();
return false;
}
}

function isAlphanumeric(elem, helperMsg){
var alphaExp = /^[0-9a-zA-Z]+$/;
if(elem.value.match(alphaExp)){
return true;
}else{
alert(helperMsg);
elem.focus();
return false;
}
}
</script>

<form onsubmit=‘return formValidator()’ action=“mypage.html” method=“post” name=“myForm” >
First Name: <input type=‘text’ id=‘firstname’ /><br />
Address: <input type=‘text’ id=‘addr’ /><br />
<input type=‘submit’ value=‘Submit’ />
</form>

The error checking works great and throws up an alert if a field is filled out. However, once everything is filled out correctly and I hit submit, nothing happens! Can anyone help? Thank you!