2003年北京市与河南省人口增长指标（%）

夏商西周时期，奴隶主维护等级制度所采取的措施不包括(     )

    Mrs White is a housewife. She is always busy in the morning. She gets up early and cooks breakfast. She has two children, Leo and May. Leo is ten years old and May is eight years old. They get up at seven o'clock. Leo makes his bed and washes quickly. May does not make her bed. Her bedroom is often messy. After breakfast, Mrs White takes them to school by car. Then, she goes to the supermarket and buys food for dinner.

    One day, Mr White has a meeting in the office. He does not come home for dinner. Mrs White is busy in the kitchen. Leo and May are waiting for dinner at the table. Leo says:” Dad isn't at home. I'm the head of our family today. I can sit on Dad's chair.” May says,” You should sit on Mum's chair.”