When you see someone who is smiling and laughing you think that that person is happy and have all she/he want and you have nothing, and that just because that person is laughing and smiling and you're always sad and you never smile but take a step back, stop that person, cover the smiling mouth and look in the eyes of that person, what do you see? You see two sad eyes which you can easily see that they doesn't slept for a while because they cried a lot. Bur you doesn't see that when you're walking besides a smiling person, aren't you? All you can see is that someone is happy and you're sad and you doesn't have anything that person have everything.