FIRST, ITS KINA WIERD THAT HE JUST STARES AT EVERYBODY LIKE THAT. Secondly, if he smiles only at you, it means he probably likes you.
they like you
You got stuff in your teeth
He is probably just messing with you. Seeing if he can get a rise out of you.
there is love
Then she probably likes him.
He is attracted to you.
he's a horny pervert who can only think about getting into your pants;)
he likes you and thinks your hot.
He probably likes you
that he's attracted to you