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.

Chinese Teachers' Day is a festival celebrating the over 2,000-year tradition of respecting teachers and education in China.

The history of Teachers' Day dates back to the Han Dynasty. According to record, during the Han and Jin Dynasties, on August 27 of the lunar calendar each year, the birthday of Confucius(孔子), the emperor would go to the Confucius Temple and worship(敬拜) the great teacher, and would also invite royal teachers to dinner. And on that day, teachers enjoyed a day's vacation and were given dried meat as gifts. Besides, best teachers who were chosen from the whole country would be given 500 liang silver coins each as prizes. In the Qing Dynasty, well performing teachers would be given official titles or promoted to higher positions.

Normally, in ancient time, there was no fixed tuition fee(学费); the parents paid with money or food.

In private schools, teachers would receive money or gifts from the host family at certain festivals or at the beginning and end of each term. The festivals in which teachers received gifts were different in different areas, while the most valued ones were the Dragon Boat Festival, Mid-autumn Festival and Chinese New Year, as well as Confucius' birthday and the private teacher's birthday.

Among all the gift-giving festivals, the first meeting gift was a must. There was a tradition that when students met their teachers for the first time, they needed to kowtow(磕头) to Confucius' picture and then to their private teachers, before giving their teachers a "gift".

Do you know that there are many things to do to keep our bodies healthy? One answer may be looking after our lungs(照顾好我们的肺). Our lungs help us breathe(呼吸), and breathing keeps us alive! So it is important to look after our lungs.

 One way to look after our lungs is by doing physical exercise often. When we play sports, our lungs must work harder. Our lungs breathe in clean fresh air. The air is used by the heart. The heart then pushes blood around different parts of our body to make them healthier.

 Another important thing is to choose to do healthy things. This means eating lots of colourful fruits and vegetables, drinking lots of water and getting enough sleep.

 But sometimes, we might meet things that aren't so good for our lungs, like smoking. When some people try to ask us to smoke, it's important to say no.

 Do you know that May 31 every year is World No Tobacco Day(世界禁烟日)? The subject this year is" Keeping Children away from Tobaccos". Countries around the world should let children know they should not smoke through the Internet.

 When we choose not to smoke, we' re not only helping our lungs. We' re also helping our body health.

Today, people all over the world have the same hobbies, watch the same movies, and wear the same clothes. {#blank#}1{#/blank#}

In the East, it can take a long time to become someone's friend. People are very close to their friends. When people from the West meet you, they will call you a friend right away. {#blank#}2{#/blank#} When people from the East meet you, they often ask questions. They want to know about your age and your family. To people from the West, these are not polite questions. They don't like to talk about these personal things. 

{#blank#}3{#/blank#} In the East, family is always a part of life. Kids there live with their parents for a long time. They still listen to them after they grow up. 

However, in the West, independence (独立) is very important. Parents prepare their kids for life. Then, after their kids grow up, they say goodbye and leave home.{#blank#}4{#/blank#} They don't have to listen to their parents. 

In the East and in the West, people think differently too. People in the West think about small de tails (细节). They also think less and act more. In the East, people notice (注意) relationships between things. And they often keep their opinions quiet.