Did you ever wonder how some of your favorite foods, products or toys came about? Believe it or not, they may have been an accident, or a failure of some other intention. Below, we found three mistakes we’re thankful for turned out to be what they are.

1. Most historians hold that the Chinese invented fireworks in the 9^th century when they discovered how to make gunpowder. Story has it that a Chinese cook accidentally mixed together what were then considered common kitchen items and noticed they burnt. When put tightly in a bamboo tube and lit, it blew up.

2. In May of 1886, a law led John Pemberton, a pharmacist(药剂师), to rewrite the formula(配方) for “Pemberton’s French Wine Coca”, his popular headache treatment. Containing sugar instead of wine as a sweetener, the outcome became something for Coke, which was later mixed with carbonated(碳酸) water. His bookkeeper suggested the name Coca-Cola because he thought the two C’s would look good together, which is how what we call Coca-Cola, a world-wide drink came into being.

3. During World WarⅡ, scientists at the University of Birmingham invented the magnetron(磁控管)—an important heat-producing part of the microwave oven. While working for Raytheon Corporation after the war, the American engineer Percy Spencer was testing the magnetron when a chocolate bar in his pocket melted. He went on to test other foods including popcorn kernels(仁), and found it to be a much more efficient way to cook. In 1947 Raytheon came out with the first restaurant microwave oven, which was six feet tall and weighed 750 lbs.
【小题1】The right time order of the three inventions should be ________.

Many cities around the world today are heavily polluted. Products (产品) arc not produced in a "green" way and people haven’t realized the importance of buying and using environmentally-friendly products. These lead to the pollution problem. One result is that millions of tons of waste like glass, paper and plastics is produced (生产). The waste problem is difficult to deal with.
However, today, more and more people are choosing “green” and expecting that the products they buy should be safe for the environment. Before they buy a product, they ask questions like these: “Will this soap be bad for the environment” “Can this metal container be reused or can it only be used once?”
Over 20,000 people took part in a web survey (调查) on buying environmentally-friendly products. Among them, 8129 people say that they now consider the environmental safety of a product before they buy it. That is to say, companies must change the way they make and sell their products to make sure that the products are “green”.
A few years ago, it was impossible to find green products in supermarkets, but now there are hundreds. Some supermarket products carry labels to show that they are green. Some companies have made the clean and safe products their main selling point in advertisements.
The growing need for a safer and cleaner environment is making companies rethink how they do business. The public will no longer accept the old idea of “buy it, use it, throw it away, and forget it”. As a result, the companies have to take action.
【小题1】Is it easy to deal with the waste problem?
【小题2】What do more and more people consider before they buy products?
【小题3】In the survey, how many people prefer green products in the supermarket now?
【小题4】Is it possible or impossible to get green products in the supermarket now?
【小题5】Why do the companies have to rethink how to do business and take action?

One in four Chinese primary school students say they are too busy to eat fruit every day, while many dislike fruit for the simple reason that their __16__tell them to eat it.
That is the result of a recent survey __17__the Chinese Association for Student Nutrition & Health Promotion(中国学生营养和健康促进协会), who last month issued a questionnaire among 1,500 children in Beijing, Shanghai and Guangzhou. They__18___ 28 percent didn't eat fruit every day and of those who did, one in seven did not eat enough.
Among students who didn't eat fruit every day, 50 percent said it was because they "didn't have time" and 40 percent of those who didn't like fruit said it was because "my parents____19___ me to".
"Fruit is a natural source of many nutritional elements(营养元素), can balance a person's nutritional intake and help to ___20___overweight(超重)," says Association director Du Yuxia.
He says about 20 percent of primary school students in Beijing and Guangzhou are overweight, while the figure is  __21___30 percent in Shanghai.
Hu Xiaoqi, a nutrition expert with the Chinese Center for Disease Control and Prevention (CDC), believes a student should eat at least 150 grams of fruit a day. Moreover, fruit juice is not an adequate substitute because the fruit __22__ contains more fiber and vitamins than juices, which are usually high in sugar and contain preservatives.
Hu says primary school students should be encouraged to eat one or two fruits every day. ___23___many students found they didn't have time to eat fruit before breakfast or in the evening, they should be encouraged to ___24__fruit to school and eat it during class breaks . Finally, she suggests that parents encourage their children to eat fruit, instead of forcing them.
Ma Guansheng, deputy ___25____of the CDC's Nutrition and Food Safety Institution(营养和食品安全机构), says: "6-12 years old is a crucial time for physical development. Children at this age need an adequate and balanced nutritional supply to guarantee the normal growth of the body."

I stood there listening to my father shout at top of his voice. The look on his face said that one of us did something .

“Which one of you did this?”

We all looked down at the step. There was child’s handwriting in chalk there. I had a lot of

. I hoped no one could see it. Would he guess it was me? I was so worried. When he asked me, I lied, “Not me, Dad.” The others denied（否认）it as well. Of course, we all knew that one of must have done it. But as the youngest and smallest of the three, I just couldn’t find the courage to tell the truth.

To who had written on the step, Father gave us each a piece of paper and a pencil. “I want each of you to exactly what you see on the step.”

I tried my best to write the words . I didn’t want Dad to be able to tell it was me.

He our pieces of paper and looked at them. “Since none of you will admit (承认) to have done it, then I will punish (惩罚) you and said nothing. The last thing I wanted was for Dad to me.

“I did it.” My sister said she did something that she didn’t. Father grounded her for a month.

We didn’t talk about that day for many years. Not until we were all older and I knew it was to finally tell my dad it was really me. I always felt sorry for it. That was the last time I let anyone take the blame (责备) for me.

1.A. hard B. wrong C. special D. true

2.A. surprise B. happiness C. fear D. joy

3.A. them B. me C. you D. us

4.A. find out B. talk about C. think about D. look for

5.A. write B. read C. recite D. draw

6.A. clearly B. slowly C. differently D. carefully

7.A. opened B. colored C. showed D. collected

8.A. only B. all C. both D. one

9.A. beat B. teach C. punish D. understand

10.A. lucky B. silly C. easy D. safe