There are three people in my family, my parents and I. My name is Li Yan. I 'm a middle school1.

    I am thirteen years old. I 'm from China, so I can speak2. I can speak a little English, too. These are my 3 .My father is a teacher in a 4 . He can speak Chinese, English and French. He teaches English. He likes 5. He often goes swimming and plays table tennis on Sunday.

    My6  is a manager. She works in a factory.7only speaks Chinese. She likes music and she can8very well. She often sings old songs. She likes white best, so her favourite season is9because it snows. Look! Here is my 10. Its name is Mimi. It is a very cute cat and I like to play with it.

设$x>0,y>0,A=\frac{x+y}{1+x+y}$, $B=\frac{x}{1+x}+\frac{y}{1+y}$，则A,B的大小关系是（    ）