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                                                        Keeping a diary—a good way to improve English

     When I was at the age of thirteen, I began to keep a diary in English. At first it seemed difficult to me, but now it has begun to be easy. I know it's not possible to learn English well without more practice, I like reading, listening and speaking. After school I often go to the school library to read English stories. My English teacher always helps me translate some passages into Chinese. 

     I have little time to watch TV, or to play computer games. After I finish writing my diary, I always try to correct mistakes with the help of the dictionary. I think that keeping a diary is one of the best ways to improve our English study. 

菜豆种子和玉米种子结构的相同点是都有种皮和____ ，结构上的主要区别是：与玉米种子相比，菜豆种子没有____ 。