Jim is an American. He is now living(居住) in China. He gets up at about half past six and has breakfast at seven o'clock. After breakfast, he says goodbye to his parents and leaves home at half past seven. He usually walks to school. He gets there at five minutes to eight. He has his first class at eight.

    Morning classes are over at ten past twelve and he has lunch five minutes later，at about a quarter past twelve. After lunch he plays with his friends.

    Afternoon classes begin at half past one. Usually there are two lessons in the afternoon. They finish at half past three. Usually he plays games or other things at school，and he gets home at about a quarter past five. He has supper at six and then does his homework and then watches TV. He goes to bed at about half past ten.

在苏联社会主义建设道路的探索中，最能发展商品经济，改善人民生活的是（　　）

下列与遗传有关的说法中，正确的是（  ）

图一表示“观察小鱼尾鳍内的血液流动实验”的第一步，图二表示显微镜下观察到的视野图象．下列各项叙述正确的是（　　）

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