Endangered dolphins are beautiful animals that needed to be saved. It may interest you to know there are about six different types of dolphins that are endangered. Many of them are river dolphins and they are very close to being lost forever if we do not take the time to care for them. The following is the reason why they are in danger.

    {#blank#}1{#/blank#}Dolphins can often get stuck(卡) in these nets and they may die. Another problem is the fact that many people and different countries will hunt for dolphins as food.

    {#blank#}2{#/blank#}When the oceans and rivers are polluted, it affects the very environment where these beautiful creatures are living. It may be important to also keep in mind that the dolphin is towards the top of the food chain.{#blank#}3{#/blank#} If these small animals are affected by the pollution as well, there really is no safe place for the dolphin to go.

    {#blank#}4{#/blank#}You can also pay attention to the land around you. Do not litter and stop if you do. Spend time on the weekend cleaning up trash in your area and recycle what you can. You play a large role in this whether you believe it or not. So, find out what your role is related to endangered dolphins and work towards a positive change.

    Napoga is a girl in Ghana, Africa. It is hard for her family to get clean water. Every morning, she leaves home at half past five to get clean water for her family in a village far away. It takes her six hours to get enough clean water for daily cooking and drinking. She has no time to go to school or to play with her friends. Millions of people in the world are like Napoga. They can't get enough clean water to keep healthy.

    Earth Day is on April 22. But on all the other days, we must also remember it. The water we use is the most important natural resource on the Earth. Water covers about 75% of the Earth's surface. But most of that is sea water. We can't use it for many things. Fresh water covers only less than 1% of the Earth's surface.

    You probably feel lucky that your life isn't as hard as Napoga's. But that doesn't mean you don't have to worry about water. We all face serious water problems. One of them is water pollution Lots of kinds of things from cars, factories, farms and homes make our rivers, lakes and seas dirty. Polluted water is very bad for people to drink. And dirty water is bad for fish too. Now, 34% of all kinds of fishes are dying out. Scientists say that in 30 years, more than half of the people in the world won't have enough clean water. We have to learn how to save more water for ourselves and our children.

    We usually think that plants always stay quiet and never speak. Grass doesn't cry when you cut it; flowers don't shout when they're picked. But this view of the world couldn't be more wrong. Plants talk to each other all the time. Their language is one of chemicals.

    Over the years, scientists have found that different types of plants, from trees to tomatoes, send compounds(复合物)into the air to help neighboring plants. But exactly how plants receive and act on many of these signals is still a mystery.

    Scientists from Kyoto University in Japan looked at tomato plants that had been bitten by insects. To start out, they grew plants in two plastic bags connected by a tube(管子). One plant had been bitten by insects. The other was not bitten.

    They found that when insects bite plant leaves, the plants don't sit quietly. They send a chemical called "hexvic" into the air. Humans can't notice it, but these chemicals carry a smell that neighboring plants can notice. This way, neighboring plants realize the danger and begin to give off more "hexvic" to protect themselves.

    The same scientists continued their research by placing insects on the plants that had not been bitten. The plants were able to kill nearly 50 percent of the invaders, much more than their neighbor.

    It was surprising that the plants that had not been bitten didn't send the chemical until the received a warning message from their infested(受侵的)neighbor, the scientists said. These findings could be used to help farmers with the control of the insects which do harm to their plants.

    Many scientists believe our love of sugar may actually be an addiction (上瘾). When we eat or drink sugary foods, the sugar enters our blood and influences parts of our brain that make us feel good. Then the good feeling goes away, leaving us wanting more. All tasty foods do this, but sugar has a particularly strong effect. In this way, it is in fact addictive, and doctors suggest we all cut down on it.

    "It seems like every time I study an illness, I find my way back to sugar," says scientist Richard Johnson. One-third of adults worldwide have high blood pressure (血压), and up to 347 million have diabetes (糖尿病). Why? "Sugar, we believe, is one of the reasons, if not the main reason," says Johnson.

    Our bodies are designed to survive on very little sugar. Early humans often had very little food, so our bodies learned to keep sugar as fat. In this way, we had energy stored for when there was no food. But today, most people have more than enough. So the very thing that once saved us may now be killing us.

    So what is the solution? It's obvious that we need to eat less sugar. The trouble is, in today's world, it's extremely difficult to avoid. From breakfast cereals to after-dinner desserts, our foods are increasingly filled with it. Some manufacturers (制造商) even use sugar to replace taste in foods that are advertised as low in fat. This may make the food appear as healthier, but large amounts of sugar are often added.

    But there are those who are fighting back against sugar. Many schools are offering more fruit instead of deserts. Other schools are building facilities for students to do exercise. The battle has not yet been lost.