假设你叫Lin Lao，Ling Ling邀请你这个周末去她家玩，请根据下面你的周末时间表，给Ling Ling写一封回信，告诉她你不能去及你周末的活动安排。(15分)

要求：1、信的内容需包括表格中的所有要点。

2、书写规范，语句通顺，行文流畅，结构完整，语法正确，无单词拼写错误。

3、字数在70以上。

1、Dear Ling Ling，

Thanks for your invitation．I'm sorry I can't visit you this weekend．I have a very busy weekend．On Saturday morning, I have to do my homework．In the afternoon I'm going to see the doctor, and in the evening I have to study for a test because I want to get good grades．On Sunday morning I'm going to have a piano lesson．In the afternoon I'm going to help my mother to do housework．In the evening I have to practice the piano．This time I can't go．Maybe next time．

    LinLao