To forgive is a virtue, but no one has ever said it is easy. When someone has deeply hurt you, it can be extremely difficult to let go of your hate. However, forgiveness is possible, and it can be surprisingly beneficial to your physical and mental health. People who forgive show less sadness, anger and stress and more hopefulness, according to a recent research.

    {#blank#}1{#/blank#}Try the following steps:

    Calm yourself. {#blank#}2{#/blank#}You can take a couple of breaths and think of something that gives you pleasure: a beautiful scene in nature, or someone you love. Don't wait for an apology. Many times the person who hurt you does not intend to apologize. They may have wanted to hurt you or they just don't see things the same way. {#blank#}3{#/blank#} Keep in mind that forgiveness does not necessarily mean becoming friends again with the person who upset you.

    Take the control away from your offender(冒犯者). Rethinking about your hurt gives power to the person who causes you pain. Instead of focusing on your wounded feelings, learn to look for the love, beauty and kindness around you.

    {#blank#}4{#/blank#} If you understand your offender, you may realize that he or she was acting out of unawareness, fear, and even love. You may want to write a letter to yourself from your offender's point of view.

    Don't forget to forgive yourself. {#blank#}5{#/blank#} But it can rob you of your self-confidence if you don't do it.

    Self-driving vehicles(车辆) will rely on cameras, sensors and artificial intelligence (人工智能) to recognize and respond to road and traffic conditions, but sensing is the most effective for objects and movement in the neighborhood of the vehicle. Not everything important in a car's environment will be caught by the vehicle's camera. Another vehicle approaching at high speed on a collision (碰撞) track might not be visible until it's too late. This is why vehicle-to-vehicle communication is undergoing rapid development. Our research shows that cars will need to be able to chat and cooperate on the road, although the technical challenges are still great.

    The usages of vehicle-to-vehicle communication contain vehicles driving together in a row, as well as safety messages about nearby emergency vehicles. Vehicles could alert each other to avoid collisions or share notices about passers-by and bicycles. From as far as several hundred metres away, vehicles could exchange messages with one another or receive information from roadside units（RSUs）about nearby incidents or dangerous road conditions through 4G network. A high level of AI seems required for such vehicles, not only to self-drive from A to B, but also to react intelligently to messages received. Vehicles will need to plan, reason, strategize and adapt according to information received in real time and to carry out cooperative behaviors. For example, a group of autonomous vehicles might avoid a route together because of possible risks, or a vehicle could decide to drop someone off earlier due to messages received, a foreseen crowding ahead.

    Further applications(应用) of vehicle-to-vehicle communication are still being researched, including how to perform cooperative behavior.

    Anger itself is neither good nor bad. It's what we do when we're angry that matters. Anger is a tool that helps us to read and respond to the social situations that bother us. But how can we keep it under control?

    It's normal to think that getting angry is bad and many times we punish ourselves for doing so. But contrary to popular belief, research indicates that anger increases optimism, creativity and efficiency (效率). In addition, studies suggest that anger can lead to more successful negotiations at work, as well as in our personal lives.

    In fact, suppressing (抑制) anger can be very bad for your health. In this sense, Dr. Ernest Harburg performed a study by monitoring a group of adults and their capacity (最大容量) for anger. What he found is that the men and women who suppressed their anger as a response to an unfair attack had a higher risk of developing bronchitis (支气管炎) or suffering from heart attacks, and were more likely to die before their colleagues who let their anger surface (显现) when they felt bothered.

    When anger arises, we feel the need to either prevent or put an end to this powerful feeling for the benefit of our welfare or the welfare of those we care about. But this act of kindness, mercy, love or justice isn't beneficial in this way. However, it's certainly a good thing to be cautious when anger begins to surface. Expressing your anger can be appropriate with certain people at certain times. The question lies in how to do it without losing control. The key to expressing your anger is finding the appropriate tone for expressing what it is that upsets you. But to avoid unnecessary shouting, hitting, or other violent reactions, it's worth taking a moment to step back and think, even though we may be in the middle of an argument with someone.

    Some materials are obtained from natural resources that are changed by chemical processes in a laboratory. The resulting artificial materials are synthetic, or human-made.

    Plastic is a synthetic substance, obtained from petroleum, a fossil fuel. The molecules（分子）in petroleum are split and then linked into chains. Plastic is an example of a polymer, a material made of repeating patterns of atoms linked together. Most polymers are synthetic. They are made by polymerization, the process of chemically linking many smaller molecules to form a larger molecule that has different physical features. Some polymers, such as proteins, occur naturally.

    Plastic is a key component of many products. When heated into an almost-liquid form, plastic can be made into fibers, sheets, or molds（模具）. It can be mixed with other elements to remain flexible, or it can harden into a solid. Plastic fibers can be made into clothing or carpeting. Sheets of plastic can be made into plates. Molded plastic can be sued for protective helmets or car bumpers.

    Most plastics can be reheated and remolded repeatedly. This feature makes plastic very easy to use. Polymers can be pulled into fine strings or molded into almost any kind of shape. For example, tubes of plastic can be shaped into bottles by different processes. One such process is extrusion blow-molding. Most plastics are also resistant to many chemicals that might harm other materials. This quality is the reason that so many cleaning liquids are packaged in plastic bottles.

    Plastics are good insulators that can stop electricity or heat to pass through. Look around your kitchen, and observe where plastics are used. Pot handles are sometimes made of plastic, as are cooking tools, toaster controls, and microwave cookware. Food-storage wraps and containers may be made of plastic. Take a walk outdoors, and note all the plastic items you see. Gardening tools, such as watering cans and sprayers, are often made of plastic. Swings and slides made of plastic do not become as hot as metal, so they are safer for play. Because plastics can be heated, remolded, and made into something else, they can be recycled and reused.

    Every new person added to the planet needs food, water, clothes, and so on. {#blank#}1{#/blank#}. Those things require extra natural resources, including land and water. But Earth's riches are limited. Less than 1 percent of Earths water can be used for drinking and washing. One out of every thirteen people around the world does not always have enough clean water.{#blank#}2{#/blank#}. Too many people are using too much water, especially in the already dry areas of the southwestern United States.

    Food shortages(不足) are even more common. Worldwide, one out of every seven people does not get enough to eat.{#blank#}3{#/blank#}. Over time, the soil loses its nutrients(营养) and the farmland becomes useless for growing food. As the world becomes more crowded(拥挤的), more land is needed to make way for growing cities. {#blank#}4{#/blank#}. That's a problem because trees help take in a gas called carbon dioxide. Humans produce carbon dioxide by burning coal and oil. Fewer trees mean more carbon dioxide in the atmosphere. The buildup of carbon dioxide traps heat and pollution above Earth.

    {#blank#}5{#/blank#}, although every person uses the planet's resources. The richest billion people, Americans especially, use the most resources. They also produce the most waste.

A. Forests are cleared away

B. Some people use a lot more than others

C. Water shortages have hit many parts of the world

D. Water pollution is a serious problem in some areas

E. More trees should be planted to handle air pollution

F. Huge needs for food force farmers to overuse their land

G. More people mean more cars, roads, schools, hospitals, and stores