I was told to smile many times by my teachers in primary school or asked why I was so sad. Smiling isn't undeniably a natural facial gesture for me, I smile to myself in the most inapropriate moments but I often feel simply foolish when I have to smile at someone's request and I'm afraid that my smile then looks a bit artificially - almost like here: http://pl.youtube.com/watch?v=1ANUP5-aW4E . Maybe I'm exagerating now, I'm a human being not a machine like a character from said scene who's learning how to smile but I am still maintaining my opinion that smile doesn't fit to my face too much.