如图，菱形ABCD中，对角线AC、BD相交于点O，不添加任何辅助线，请添加一个条件 ____，使四边形ABCD是正方形（填一个即可）．

   We do the shopping on Sundays . I often go to the supermarket with my mother on Sunday morning in a car . Father likes fruit very much. We buy some red apples for him. Mother likes yellow bananas , but they're green. "Look! The strawberries are very nice, mum. Do you like them?" I say to Mum. "Yes, I like strawberries very much . " Mother buys some for herself. The oranges are very nice. Mother buys some for me . I like orange very much.
   We need some vegetables . The vegetables in the supermarket are very good . We buy some tomatoes, carrots and broccoli . I don't like broccoli, but my parents like it . I like carrots very much. We buy lots of carrots. After shopping , mother and I have some French fries, milk and ice cream. And then we go back home with the fruit and vegetables .

根据自己的理解，结合你的生活经历和感悟，写一篇600字左右的记叙文，力求写出真切体验与独特感受。文中不得出现真实的校名与人名。