Dear Dr. Know,

I'm very glad to write to you. I have a lot of troubles these days. Every day I have a lot of homework to do at school. I don't enough time to sleep. I nearly have no time to do sports. My friends and I can hardly find time to talk, or play together. When I get back home from school, I'm not allowed to watch TV, surf the Internet or listen to my favourite music. I feel worried about them. I don't know what I should do. Could you please give me some sugestions?

Yours,

Li Ping

题目分析：根据提示给Dr. Know 写一封信，可知这是一封信，所以所写的短文格式一定是符合信的格式。根据内容学习任务重，睡眠不足，缺少体育活动，同学之间的关系。在家不允许看电视或上网等等，可知短文应该用一般现在时，来叙述平时的自己的烦恼。

【亮点说明】短文用了一些短语和句式，为文章增色不少，如：My friends and I can hardly find time to talk, or play together. When I get back home from school, I'm not allowed to watch TV, surf the Internet or listen to my favourite music. 等，文章还用了一些连词如：when和what等，使句子的结构复杂化了。