skeletal structure of dimethylamine? HN(CH3)2 I don't understand how to draw this skeleton. 
 I know there is a NH2 in an amine structure, but this only has NH? 
and dimethyl means there a 2 identical single side chains right? but where on the skeletal structure are they? 
I'm totally stuck as to how the skeletal structure is supposed to look.
Please look at the skeletal structure of different types of amines:



I hope it's clear now.