“Without music, life would be a mistake,” famous German philosopher(哲学家) Friendrich Nietzsche said over a century ago. Music is a big part of our lives. But in recent years, some US schools have cut music classes to control budgets(预算).

    For example, Chicago public schools hurt arts education when it fired(解雇)over 1,000 teachers. Among them, 10 percent of the teachers taught art or music, according to The Washington Times. In fact, this is not just a problem in the US. In other countries, such as China and the UK, music classes are not thought to be as important as ones like science, math and history. That's partly because music is not seen as a very important life skill, and it isn't tested. Many students are busy with schoolwork, so parents and students choose to focus on subjects that are tested more often.

    However, learning music is beneficial(有益的)in many ways.

    When playing music, you need different abilities to work together. It is not as simple as it looks, according to Kenneth Guilmartin of Music Together, an early childhood music development program. For example, when playing the piano, people see music notes and decode(解码)them in their brains. They also use their fingers to make sounds. You need to deal with all these things at the same time.

    Music has a special connection with science as well. You can see that many scientists are good at playing music: Einstein played the violin, and German physicist Max Planck was talented in playing the piano.

D

    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.

    The world is not hungry, but it is thirsty. It seems strange that nearly 3/4 of the Earth is covered with water while we say we are short of（短缺）water. Why? Because about 97% of water on the Earth is sea water which we can't drink or use for watering plants directly(直接地）. Man can only drink and use the 3%-the water that comes from rivers and lakes. And we can't even use all of that, because some of it has been polluted(污染）.

    Now more water is needed. The problem is Can we avoid（避免）a serious water shortage later on? First, we should all learn how to save water. Secondly, we should find out the ways to reuse it. Scientists have always been researching in the field. Today, in most large cities water is used only once and then runs to the seas or rivers. But it can be used again. Even if(即使）every large city reused its water, there would not be enough. What can people turn to next?

    The seas seem to have the best answer. There is a lot of water in the seas. All that needs to be done is get the salt out of the sea water. This is expensive, but it's already used in many parts of the world. Scientists are trying to find a cheaper way of doing it. So you see, if we can find a way out, we'll be in no danger of drying up.

    Now too much CO makes the Earth warmer and warmer, and brings bad effect to people. To save our Earth, a new lifestyle called low-carbon life becomes popular. Low carbon means low energy and no waste. It is necessary for everybody to learn to live a low-carbon life.

    To live a low-carbon life, we'd better save as much energy as we can. For example, turn off the lights and TV when you don't use them, use cold water to wash clothes or dishes: take a short shower and try to take a cold one when the weather gets warm: don't do the cooking with electricity.

    To live a low-carbon life, we should eat less meat. Being a vegetarian can help reduce (v)one and a half ton of carbon dioxide a year, but keeping animals for food produces even more carbon dioxide than all the cars do in the world.

    To live a low-carbon life, we should plant more trees. Trees are very important for us. They can not only produce oxygen for us to breathe and keep the air clean. But also take in the harmful gases from the air. To protect trees we should stop people from cuing down trees and plant as many trees as we can.

    If we can keep them a habit in our daily life, the earth will become a safer planet for us to live on.