Prototype Ajax error?

[Swapsry]

Hi frnds...

I am new to AJAX....now i m trying to learn Prototype AJAX...
here i have a doubt, plz check this one....

new Ajax.Request("submit.php", 
					{ 
					method: 'post', 
					[B]postBody: 'name='+ $F('name')
					 'mobile='+ $F('mobile')
					 'email='+ $F('email')
					'address='+ $F('address'),[/B]
					onComplete: showResponse 
					});

here how can i send more number of variables....(bold part)..plz correct it...

Also plz send me some good tutorials,EBooks of PROTOTYPE Ajax....

Thanks in advance...