There are an extremely large number of ants worldwide. Each individual (个体的) ant hardly weigh anything, but put together they weigh roughly the same as all of mankind. They also live nearly everywhere, except on frozen mountain tops and around the poles. For animals their size, ants have been astonishingly successful, largely due to their wonderful social behavior.

    In colonies (群体) that range in size from a few hundred to tens of millions, they organize their lives with a clear division of labor. Even more amazing is how they achieve this level of organization. Where we use sound and sight to communicate, ants depend primarily on pheromone (外激素), chemicals sent out by individuals and smelled or tasted by fellow members of their colony. When an ant finds food, it produces a pheromone that will lead others straight to where the food is. When an individual ant comes under attack or is dying, it sends out an alarm pheromone to warn the colony to prepare for a conflict as a defense unit.

    In fact, when it comes to the art of war, ants have no equal. They are completely fearless and will readily take on a creature much larger than themselves, attacking in large groups and overcoming their target. Such is their devotion to the common good of the colony that not only soldier ants but also worker ants will sacrifice their lives to help defeat an enemy.

    Behaving in this selfless and devoted manner, these little creatures have survived on Earth, for more than 140 million years, far longer than dinosaurs. Because they think as one, they have a collective (集体的) intelligence greater than you would expect from its individual parts.

    Life in the Clear

    Transparent animals let light pass through their bodies the same way light passes through a window. These animals typically live between the surface of the ocean and a depth of about 3,300 feet—as far as most light can reach. Most of them are extremely delicate and can be damaged by a simple touch. Sonke Johnsen, a scientist in biology, says, “These animals live through their life alone. They never touch anything unless they're eating it, or unless something is eating them.”

    And they are as clear as glass. How does an animal become see-through? It's trickier than you might think.

    The objects around you are visible because they interact with light. Light typically travels in a straight line. But some materials slow and scatter(散射) light, bouncing it away from its original path. Others absorb light, stopping it dead in its tracks. Both scattering and absorption make an object look different from other objects around it, so you can see it easily.

But a transparent object doesn't absorb or scatter light, at least not very much, Light can pass through it without bending or stopping. That means a transparent object doesn't look very different from the surrounding air or water. You don't see it —-you see the things behind it.

    To become transparent, an animal needs to keep its body from absorbing or scattering light. Living materials can stop light because they contain pigments(色素) that absorb specific colors of light. But a transparent animal doesn't have pigments, so its tissues won't absorb light. According to Johnsen, avoiding absorption is actually easy. The real challenge is preventing light from scattering.

Animals are built of many different materials—-skin, fat, and more—-and light moves through each at a different speed. Every time light moves into a material with a new speed, it bends and scatters. Transparent animals use different tricks to fight scattering. Some animals are simply very small or extremely flat. Without much tissue to scatter light, it is easier to be see—through. Others build a large, clear mass of non-living jelly-lie(果冻状的)material and spread themselves over it .

    Larger transparent animals have the biggest challenge, because they have to make all the different tissues in their bodies slow down light exactly as much as water does. They need to look uniform. But how they're doing it is still unknown. One thing is clear for these larger animals, staying transparent is an active process. When they die, they turn a non-transparent milky white.

    It was dawn of March 21, 2018. Gary Messina was on his morning run along New York City's East River. Suddenly something caught his eye – a large 60-year-old man balancing on the four-foot-high fence that guarded the path from the water. As Messina got closer to the scene, the man took a step forward and slipped into the dark river below.

    When Messina reached nearer, the man was struggling in the water, clearly unable to swim. Other joggers also heard the man's cry. David Blauzvern and John Green dropped their phones and keys on land and jumped in. “People had called the police, but it was unclear when they'd get there.” says Green. “We just reacted.” Messina joined them in the river. Just as the jumper was losing strength, Blauzvern take hold of him. The pair were about 30 yards from the seawall when Messina and Green caught up to them. They seized the man, with Blauzvern supporting his back and Messina and Green holding him up from either side. As the men made their toward the concrete seawall that stretched (延伸) for blocks in each direction, Blauzvern had an awful realization: there was no way out of the river.

    By now, a crowd had gathered on land. “A rescue boat is on its way,” someone yelled to them. Swimming forward was getting tougher by the minute. The jumper, who was six foot two and weighed around 260 pounds, was heavy in his rescuers' arms. After ten minutes, they managed to get to the river's edge. “I've never been so out of breath,” says Blauzvern.

    Fifteen minutes after the men had jumped into the river, the two-man rescue boat appeared. But because it couldn't risk getting too close to the seawall, the men had to swim out to it. “I was completely out of energy at this point,” says Blauzvern. The men in the water pushed the jumper while the men in the boat pulled him up and, finally, to safety. The man they had saved was taken to the hospital for evaluation(评估). Details on his condition have not been known. As for the rescuers, each of them was at work by 10:30 a.m. “I was a bit late,” admits Blauzvern, smiling. “But I had a good excuse.”

    Meeting people from another culture can be difficult. From the beginning, people may send the wrong signal. Or they may pay no attention to signals from another person who is trying to develop a relationship.

    Different cultures emphasize the importance of relationship building to a greater or lesser degree. For example, business in some countries is not possible until there is a relationship of trust. Even with people at work, it is necessary to spend a lot of time in "small talk", usually over a glass of tea, before they do any job. In many European countries, like the UK or France, people find it easier to build up a lasting working relationship at restaurants or cafe rather than at the office.

    Talk and silence may also be different in some cultures. I once made a speech in Thailand. I had expected my speech to be a success and start a lively discussion, instead there was an uncomfortable silence. The people present just stared at me and smiled. After getting to know their ways better, I realized that they thought I was talking too much. In my own culture, we express meaning mainly through words, but people there sometimes feel too many words are unnecessary.

    Even within Northern Europe, cultural differences can cause serious problems. Certainly, English and German cultures share similar values, however, Germans prefer to get down to business more quickly. We think that they are rude. In fact, this is just because one culture starts discussions and makes decisions more quickly.

    People from different parts of the world have different values, and sometimes these values are quite against each other. However, if we can understand them better, a multicultural environment will offer a wonderful chance for us to learn from each other.

    It seems that in many places storms visit more often. When a storm is coming, most people leave the area as quickly as possible and head for safety. But there are a few people who will get into their cars and go straight for the center of the storm. These people are willing to risk being killed by floods or 100-kilometer-an-hour winds for the excitement of watching the storm close up.

    "Storm chasing" is becoming an increasingly popular hobby, especially in the Midwest of the United States, where there are frequent storms between March and July. A storm chaser begins the day by checking the Internet for the latest weather reports, and then drives up to 1,000 kilometers to where the storm will be and waits for it to develop.

    Although anyone can do it, storm chasing is extremely dangerous. The power of a big storm can throw a cow into the air or destroy a whole house in seconds. Storm chasers are also often hurt in accidents caused by driving in a heavy rain. If you are a beginner, it is much safer to join a group for storm-chasing vacations during the storm season.

    Even then, storm chasing is not all adventure and excitement. "Storm chasing is 95% driving," says Daniel Lynch, who spends most of his summer storm-chasing. "Sometimes you can sit around for hours waiting for something to happen, and all you get is blue sky and a few light showers."

    However, for storm chasers, it is all worth it. "When you get close to a storm, it is the most exciting sight you will ever see in your life," says Jasper Morley. "Every storm is an example of the power of nature. It is the greatest show on Earth."

    King's College Summer School is an annual (年度的) training program for high school students at all levels who want to improve their English. Courses are given by the teachers of King's College and other colleges in New York. Trips to museums and culture centers are also organized. This year's summer school will be from July 25 to August 15. More information is as follows：