A great white shark in a California aquarium attacked two soupfin sharks(翅鲨), causing their deaths. The attack was not a natural action for food, but a kind of response when the two sharks swam too close to the great white. The great white didn't attacked other fellows, but the officials had to move other soupfin sharks to another tank(贮水池)for their safety.

    These attacks had given rise to calls for the freedom of the 88-pound, 5-foot-3- inch shark. The aquarium housed the shark in a huge tank. However, according to experts, the tank was not big enough for the shark. Its nose was bloody from striking the glass of the aquarium. Great white sharks in the wild had a big amount of migration, sometimes traveling 50 miles a day. Because the shark was still young, there was possibility of his growing. As it grows, it can became more troubled in the limited space.

    Aquarium officials said that keeping the shark in the aquarium allowed them to study their behavior that they cannot study with free great white sharks. When they studied behavioral patterns, scientists believed that they can help great white sharks in the wild.

    Since the shark had been on display, the number of people who visited aquarium increased greatly. The one-year-old shark was the longest surviving great white living here. It had been at the Monterey Bay Aquarium for six months. Other great whites did not survive for longer than 16 days in the aquarium.

    Last month, the president of the Maldives, Mohamed Nasheed, held an underwater meeting. The purpose of the ocean floor conference is to highlight the effects of global warming on his island nation.

    The Maldives, located in the Indian Ocean, is the lowest-lying country on Earth. Melting glaciers and polar ice are causing sea levels to rise, putting the Maldives and other low-lying areas at risk of being swallowed by the sea within the next 100 years.

    What can be done? Scientists and leaders from 190 nations will try to figure that out at the United Nations climate change conference next month. The main goal of the meeting is to come up with a new climate agreement for 2012 and beyond. That is when the existing plan, the Kyoto Protocol will expire. The agreement was created in Kyoto, Japan, in 1997. Since then, it has been ratified(正式批准) by 190 nations. The countries promised to limit the amount of greenhouse gases, such as carbon dioxide, which they produced each year.

    The debate over who should cut greenhouse emissions has been going on for years. The US has been hesitant to reduce emissions unless fast-growing nations such as China and India also reduce their use of fossil fuels. In recent months, China has taken steps to be greener. But India has been unwilling to change. It argues that it is unfair for rich nations to ask poorer countries to cut down on emissions.

    While world leaders work on a plan in Copenhagen, there are many things you can do to help the planet. You can save fuel by walking or biking instead of riding in a car. You can start a recycling program in your community. You can plant trees. Trees absorb carbon dioxide from the air and give off oxygen.

    The days of the hunter are almost over in India. This is partly because there is practically nothing left to kill, and partly because some steps have been taken, mainly by banning tiger-shooting, to protect those animals which still survive.

    Some people say that Man is naturally a hunter. I disagree with this view. Surely our earliest forefathers, who at first possessed no weapons, spent their time digging for roots, and were no doubt themselves often hunted by meat-eating animals.

    I believe the main reason why the modern hunter kills is that he thinks people will admire his courage in overpowering dangerous animals. Of course, there are some who truly believe that the killing is not really the important thing, and that the chief pleasure lies in the joy of the hunt and the beauties of the wild countryside. There are also those for whom hunting in fact offers a chance to prove themselves and risk death by design; these men go out after dangerous animals like tigers, even if they say they only do it to rid the countryside of a threat. I can respect reasons like these, but they are clearly different from the need to strengthen your high opinion of yourself.

    The greatest big-game hunters expressed in their writings something of these finer motives. One of them wrote.

    “You must properly respect what you are after and shoot it cleanly and on the animal's own territory(领地). You must fix forever in your mind all the wonders of that particular day. This is better than letting him grow a few years older to be attacked and wounded by his own son and eventually eaten, half alive, by other animals, Hunting is not a cruel and senseless killing - not if you respect the thing you kill, not if you kill to enrich your memories, not if you kill to feed your people.”

    I can understand such beliefs, and can compare these hunters with those who hunted lions with spears(矛) and bravely caught them by the tail. But this is very different from many tiger-shoots I have seen, in which modern weapons were used. The so-called hunters fired from tall trees or from the backs of trained elephants. Such methods made tigers seem no more dangerous than rabbits.

    First-time shoppers at Seattle-based Amazon Go may feel as though they were stealing. That's because the 1,800 square-foot grocery store, which opened its doors to the public on January 22, has no cashiers or even checkout counters. Instead, as the name indicates, customers merely grab what they need and go! But before you start celebrating, the goods are not free—the cost of the purchase(s) is/are calculated electronically using “Just Walk Out” technology.

    The process is simple. Upon entering the store, shoppers “sign-in” by scanning their smartphones. Every item selected gets added to the bill automatically. If the customer changes his mind, all he has to do is return the purchase to the shelf, and it will be removed from the final bill. Though consumers will not find everything they need, they will be able to buy basics like bread, milk, and drinks. There are also numerous ready-to-eat breakfast, lunch, and dinner choices made by chefs in the on-site kitchen. Those that prefer to cook at home can select from the wide variety of Amazon Meal Packages.

    Once the customer exits the store, the system processes the purchases and charges the cost to their Amazon account. Within seconds, the customer is notified of the deal with a digital receipt that lists each item bought, as well as the time spent in the store. The accurate tracking is possible thanks to multiple smart cameras that monitor everything the shopper is doing. Kumar explains,“Cameras figure out which interactions(互动) you have with the shelves. Computer vision figures out which items are taken. Machine-learning also determines which item it is.” The company insists that the system is so accurate that shoplifting(偷盗) is impossible. And they should know, considering that Amazon employees have been shopping there since 2015!

    The store has raised some concern about the jobs of the over 3.5 million cashiers in America. However, Amazon officials say they have nothing to worry about because human employees are not being displaced. They are simply assigned other essential tasks, like preparing meals, restocking shelves, assisting customers, and solving technical issues.

There are various ways in which to read body language so that you can understand how someone is feeling.

Reading emotional clues (线索)is one of them.

Crying is considered to be caused by an explosion of emotion in most cultures.Often times crying is considered a sign of sadness,but crying can also be an expression of happiness.Crying can also come about through laughter and humor.Thus,when judging crying,you'll need to look for other signs to determine the meaning of the crying.Crying can also be forced in order to gain sympathy or to cheat others.This practice is known as "crocodile tears",an expression that draws on the wrong idea that crocodiles"cry" when catching prey(猎物).

Signs of threat include v-shaped eye brows, wide eyes, and an open or down-turned mouth.In a similar way, arm tightly crossed over the other is a common sign that the person is angry and is closing himself off to you.

When people show anxiety, they display increased facial movements, and their mouth made into a thin line.

Individuals who are anxious may also play with their hands, unable keep them in one spot.Anxiety can also or have nervous legs.It can be conveyed when people seemingly unconsciously(无意识地)tap their feet or have nervous legs.

Embarrassment can be expressed by turning the eyes or shifting them away.If someone looks down at the floor a lot,they are probably shy,afraid,or embarrassed.People also tend to look down when they are upset,or trying to hide something emotional.People are often thinking and feeling unpleasant emotions when they are in the process of staring at the ground.

There are also some signs of pride.People show pride by displaying a small smile,holding their head backward,and putting their hands on their hips.