13岁，花一样的年华，本该做着七彩斑斓的梦，但严慧却早早扛起了家庭的重担，6岁时，小慧的妈妈离家出走，爸爸在外打工，她就一个人承担起照顾失明奶奶的责任。2015年11月，小慧的爸爸因病去世，家中唯一的经济来源也断了，还欠下20多万的债务。生活的不幸没有把她打垮，反而让她变得更强大。对于巨额债务，她承诺“我以后赚了钱肯定一分一分还清”；在家里，她除了照顾奶奶的饮食起居，还要除草、种菜、做饭、洗衣服；在校内，她勤奋好学，成绩优异；在校外，她时时处处做“小雷锋”，扶助老弱病残等。

柔弱的肩膀，强大的力量。我们应该怎样以她为榜样，成为一个力量强大的人？

无原无故____    无可耐何____    流光益彩____    千均一发____

异想不到____    目登口呆____    独出心载____    一如即往____

如图，已知抛物线$l_1$:$y=\frac{1}{2}{x}^2-2x$与x轴分别交于O、A两点，它的对称轴为直线x=a，将抛物线向上平移4个单位长度得到抛物线，则图中两条抛物线、对称轴与y轴所围成的图形（图中阴影部分）的面积为

    If you remember the following six ways of information, you'll know how to protect yourself. You'll be much safer at school and in your everyday life.

1)Always notice the environment around you. You shouldn't walk alone out. Make sure where the public phones are. If anything dangerous happens, you can find them quickly.

    Don't use earphones when running in the schoolyard or on the street. You will keep yourself from the outside world and can easily get into trouble.

    When taking a bus, school bags should be carried towards the front of your bodies instead of putting them on your backs. When buses are crowded, it is easy enough for thieves to steal the things in the bag on your back.

    If you are followed by a stranger, cross the street and go in the other direction. Let the stranger know he or she is there. Next, go and get help from others if it is necessary. Don't go home directly. You are safer in the street than you are in your home or in a lift.

    If you have to take a bus to a place far away, try to get to the stop only a few minutes before the buses leave. On buses, don't sit alone. You should sit behind the driver or with friends. Don't sleep.

    Don't play with matches or candles, because it may cause fire. If your house catches fire and you have to escape through smoke, move on your hands and knees with your head 30-60 centimeters above the floor. Please remember there is cleaner and cooler air near the floor during the fire.

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