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    Almost every Chinese person can recite(背诵) the two lines of the famous poem, "Every grain on the plate comes from hard work". But sadly, many of us don't actually get the real meaning of these lines: Don't waste food.

    A CCTV program reported that the food Chinese people throw away every year is enough to feed 200 million people for a year. Do we have too much food? Absolutely not. According to the UN World Food Program, there were 925 million hungry people around the world in 2013, especially in developing countries. Six million children die of hunger every year.

    Chinese people are well-known for being friendly and generous. Many even feel that they lose face if their guests have eaten all the food on the table. Luckily, a number of people have realized the importance of saving food. What should we do in our daily lives to waste less food?

    ⒈ Don't order too much in a restaurant. Only order as much as you want to eat. If you cannot eat all the food you ordered, take the rest of it home.

    ⒉ Don't leave any food in your bowls while having meals.

    ⒊ Keep an eye on what food you have at home. Don't buy too much, especially for vegetables and fruit.

    Water is very important to us. Every day we drink water, cook with water, take a shower in water, and have many other activities with water. Let's read and learn more about it!

    70percent of an adult's body is water. And about 80percent of a baby's body is water.

    Drinking too much water q{#blank#}1{#/blank#} can cause water intoxication (醉).

People should have about eight c{#blank#}2{#/blank#} of water every day.

    By the time you feel thirsty, your body has l{#blank#}3{#/blank#} over one percent of its water.

    About 80percent of the Earth's surface is covered with water.

    Only one percent of this water is fresh, 97percent is salt water and two percent is f{#blank#}4{#/blank#} in glaciers (冰川).

    And now, it's time to s{#blank#}5{#/blank#} water!

You might have seen beautiful rainbows in the sky before. They form when sunlight falls on water drops in the air. But in fact, moonlight can also create rainbows in the same way. They are called "moonbows". They are similar to rainbows, but they are created by moonlight instead of direct sunlight.

Moonbows are less common than rainbows. Different weather and astronomical(天文学的) conditions have to be just right for moonbows to be created.

The moon has to be very low in the sky-only 42 degrees from the horizon(地平线). The moon period has to be a full moon or nearly full. The sky must be very dark for a moonbow to be watched clearly-any bright light can obscure it. Water drops must appear in the air in the opposite direction of the moon.

Moonbows appear on the opposite side of the moon and usually look white to the human eye. This is because their colors are not bright enough to be noticed by the human eye. It is possible, however, to view the colors in a moonbow using long exposure (长时间曝光) photography.

Moonbows more often appear in some locations around the world. Most of these locations usually have waterfalls, which create thin fog in the air. Some of these locations are the Yosemite National Park in California and Cumberland Falls State Resort Park in Kentucky, US; Victoria Falls on the border of Zambia and Zimbabwe; and Waimea in Hawaii, US.

Moonbows do really happen. So at a certain time and a certain place, when a moonbow happens to appear, you can't miss it if you're right there.

March 14 is a great day for fans of maths. It is celebrated as Pi(π) Day, a day to celebrate the number that many people know very well. The date copies from the first three numbers of Pi(π). March is the third month and the 14th means one and four. Altogether it is 3.14. Pi(π) comes wherever there are circles(圆). Pi has been known for thousands of years and gets its name from a Greek letter, n. The Greeks are believed to be the earliest to use the letter in maths. The first Pi Day was celebrated on March 14,1988.

San Francisco's Exploratorium Science Museum started the event. The museum marks the day with a daylong celebration. March 14 is also the birthday of the famous scientist Albert Einstein. Princeton University, where Einstein lived for many years, celebrates Pi Day as well. March 14,2009, was celebrated as National Pi Day. And March 14,2019 also marked the one- year anniversary(周年纪念[1]) of the death of Stephen Hawking. And how do people celebrate the Pi(π) Day? Maybe you can try these ideas:

Eat or make different kinds of pies(for example, apple pies, cherry pies, and even pizza pies);

Celebrate the day with a pie cut using the mathematical constant(常数) of Pi(π);

Discuss the importance of the letter π;

Watch Life of Pi in cinemas;

Look for the number 3.14 in every place(such as prices and street numbers).

 In a small town. {#blank#}1{#/blank#}(对话) about education were common. People often discussed how to make students more {#blank#}2{#/blank#}(积极) in learning. One day, a group of teachers decided to teach {#blank#}3{#/blank#}(物理) in a fun way. They {#blank#}4{#/blank#}(创造) interesting activities to help students understand difficult topics.

 During a meeting. a teacher shared the school's {#blank#}5{#/blank#}(地址) so parents could visit and see the students` progress. The school head said that {#blank#}6{#/blank#}知识) should be shared openly, and learning should be clear and {#blank#}7{#/blank#}(真按) so everyone could benefit. As more students became interested, their understanding of science {#blank#}8{#/blank#}(增加).

 Later, two {#blank#}9{#/blank#}(警察) visıted the school and {#blank#}10{#/blank#}(赞赏) the students' achievements. They saw how the new teaching methods had helped the children learn more and succeed in their studies.