2015年8月2日，国务院发布的关于全面实施城乡居民大病保险的意见提出，2015年底前，大病保险覆盖所有城镇居民基本医疗保险、新型农村合作医疗参保人群，大病患者看病就医负担有效减轻。这体现的政治生活道理有（  ）

①我国是人民民主专政的社会主义国家      ②人民民主的本质是公民当家作主

③社会主义民主具有真实性                ④人民当家作主的权利有法律保障

曲线$y=x^3$在点（1，1）处的切线与x轴及直线x=1所围成的三角形的面积为（  ）

    What will our world be like in 2050? A group of experts has made____(they) predictions about our life.

    It is____(believe) that we will have “clever”cars by 2050. We won't have so many accidents b____they will probably be able to communicate with each other. Cars will slow down by themselves or stop in____(danger) situations.

    What's more we will never d____! Our brains will be put onto computers and we can live forever. The computers of____future won't look like machine. They'll look like____

    By 2050 there will be less____ (pollute). The factories will be ____(build)on the moon and other planets. We will be able to spend holidays on Mars and be back ____ spaceship in just a few days.