March 25 is called the National Day of Education on the Safety of Elementary and Middle School Students. The theme of the day {#blank#}1{#/blank#} (这个) year is to give students more knowledge about safety and make {#blank#}2{#/blank#}(确信) their lives safe.

    What can we do to keep {#blank#}3{#/blank#} (我们自己) safe? Staying calm is the first and most {#blank#}4{#/blank#} (重要的) rules when facing accidents.

    When there is a fire， follow the te2tchers' instruction, leave the classroom {#blank#}5{#/blank#} (迅速地) and use a piece of cloth to cover your mouth and nose so that you don't breath in {#blank#}6{#/blank#}(烟雾).

    A stampede(蜂拥) is possible {#blank#}7{#/blank#} (任何地方). The larger a human crowd get, the more likely stampede become. When students around you begin to {#blank#}8{#/blank#}(推), stand still and try not hold onto something, or stay in a corner {#blank#}9{#/blank#}(直到……为止) the crowd leaves.  If you fall down in a moving crowd, cover your head with both {#blank#}10{#/blank#} (手).

    Playing sports is a lot of rum getting hurt isn't! Before playing sports, you should warm up for 15 to 30 minutes,

    Thousands of years ago, people used different ways to measure things. Some people used the s{#blank#}1{#/blank#}of their king s foot or hand to measure things. After the king died, they used the new king's foot or hand, and so on. However, it was i{#blank#}2{#/blank#}for people to tell the exact size of a thing. In 1584, the Dutch(荷兰的) engineer Simon Steven started to think about a set of measures, The measures used the number ten. H{#blank#}3{#/blank#}, it was just an idea. No one was interested in his idea at that time.

    About two hundred years later, the French scientists created a n{#blank#}4{#/blank#}system of units, using Simon Steven's idea. Around this time, the French scientists w{#blank#}5{#/blank#}out the length of a metre and began to use metres to measure length. They decided to c{#blank#}6{#/blank#}a hundredth of a metre a centimetre and a thousand metres a kilometre.