You shouldn't say mean things to people.
A girl in Janet's class has lost a little weight and asks Janet how she looks.
Janet wants to answer the girl.
Janet tells the girl that she looks great and congratulates her on her weight loss.
Janet tells the girl that she is such a fat pig that the little weight she lost barely makes a difference.
The girl feels happy that her hard work at losing weight has paid off.
The girl is crushed by Janet's remark and runs away crying.