Forget lions, tigers and bears. When it comes to the art of war, army ants are among the top on Earth. And one of the best places to study army ants is Barro Colorado, an island home to as many as 50 colonies (群体) of Eciton burchellii, the most studied army ant in the world.

The colonies of this army ant are huge, including 300,000 to 700,000 ants. With their legs joining together, they are able to use their own bodies to make huge nests (巢穴). There they stay for about 20 days as the queen lays as many as 300,000 eggs. When the ants go out looking for food, about 200,000 of them leave the nest in a group, forming a fan as wide as 14 metres across. Amazingly, they travel a different way each day to cover fresh ground.

Protecting the ants wherever they go are the soldiers. You can tell a soldier ant from others easily by its unusual, oversized jaws (下巴). The soldiers are very good at fighting with these powerful jaws. But the fights are always deadly. Because of the special shape, it’s impossible for a soldier to pull its jaw out again, so it actually kills itself in a fight. Local people often use soldier ants to close wounds, by breaking off their bodies and leaving the heads in place.

Eciton burchellii are blind and can’t see what’s in front of them, but they move together in such great numbers that they can easily kill the non-army ants, and other small animals. When the group meet a break on the way, ants immediately join their legs together and form a living bridge so that they can keep moving forward.

In fact, army ants can totally depend on their fellow ants. There are good examples of these ants dying for others, which is certainly more than what many of us can do.

What should we do if one of our classmates suddenly falls ill or gets hurt? Here are some steps you should follow. But always remember to look for medical care after first aid if the wound is serious.

Broken bones: Take away clothing from the wound. Use an ice pack. Don’t move the hurt body part while waiting for the doctor to arrive.

Animal bites (咬伤): Wash the bite area with soap and water quickly. Pack the wound with a clean cloth if it is bleeding. If the bleeding has stopped, cover the area with a bandage and take the person to the hospital. Make sure you remember what kind of animal it is, so the doctor can find the right way to treat him or her at once.

Fainting (昏厥): Have him or her lie with feet lifted a little. Don’t move the body if you think there might be wounds from the fall. Make sure he or she can breathe and let in fresh air. Clean the person’s face with a cool cloth.

Nosebleeds: Have the person sit up with his or her head tilted (倾斜) forward a little. Do not have the person tilt his or her head back because this may cause heavy breathing or coughing. Pinch (捏) the lower part of the nose for at least 10 minutes.

Hawaii is famous for its beautiful beaches. Every year water sports, especially surfing and water skiing attract tourists to the island.

Hawaii has been a magical name to people who like to travel for many years. People on both sides of the Pacific Ocean(太平洋), in Japan and in America, dream of   seeing   these beautiful islands in the middle of the ocean. In the tropical lands, the sun drops like a ball of golden fire into the sea, and it drops so quickly that you can almost see it move. The sun leaves behind a glow that lights the sky in the quiet water.

People often have a quiet, enjoyable time walking along the water. This scenery here is not very different from the exciting beauty that greeted the first tourists to these islands centuries ago. They came in canoes not much bigger than small boats.

They found the beautiful white sand beaches and the waving palm trees, but there were no grand hotels like the one we see today. The first people came to Hawaii nearly two thousand years ago, but skyscraper hotels were only built in the last 25 years. Now planes make it possible to fly to Hawaii for a weekend from Tokyo or San Francesco.

No matter where people come from, they really want to see the earliest beauty of Hawaii. They want to see the lovely beaches and the mountains which are almost hidden by the tall hotels.