Millions of people along the US mid-Atlantic region should be preparing for severe snow, the National Weather Service has said. Forecasters say two feet of snow could fall over the weekend in some areas. A light dusting of snow on Wednesday night caused a traffic jam in Washington, but it is what lies ahead that is occupying the thoughts of millions of people living on the US east coast.

    Washington Mayor Muriel Bowser tweeted an apology to her constituents(选民), saying that the city government had “failed to use the necessary resources effectively in response to the snow-for that I am sorry.” Among those affected was President Barack Obama, whose motorcade spent an hour and 12 minutes trying to get him from an airport back to the White House-a trip that typically takes about a half hour.

    Routine commutes lasted up to three hours and some people abandoned their cars, after an inch fell-a small amount compared to what is expected on Friday and Saturday. Long queues have formed at supermarkets, as people expect shop closures over the weekend. “Heavy snow and blowing snow will cause dangerous conditions and will be threat to life and property,” the National Weather Service warned.

    Across the US east coast at a glance:

    Classes were cancelled at schools in Kentucky and Tennessee, the first states being affected by the storm.

    Washington has requested Humvees from the National Guard so that emergency responders can reach isolated(孤立的) people and places. Besides, its underground train system will close throughout the weekend.

    West Virginia Govemor Earl Ray Tomblin has activated the National Guard to assist.

    In Philadelphia, Pennsylvania officials are calling on people to keep large salt stockpiles and plough vehicles in good repair.

    There is a breakthrough in building aircrafts. Bendable wings covered with overlapping(部分重叠) pieces resembling fish sizes could be used to build swifter, fuel-efficient aircraft, a new study finds.

    Nowadays, conventional aircrafts typically rely on ailerons (副翼) to help control the way the planes tip as they fly. However, when the Wright brothers flew the first airplane, Flyer 1, over a century ago, they used no ailerons but wires and pulleys that twisted the wood-and-canvas wings, to control the plane.

    Scientists have long sought to develop aircrafts that can alter their wings during flight, just as birds can. However, most previous attempts have failed because they relied on heavy mechanical control structures within the wings. These structures were also complex and unreliable, said Neil Gershenfeld, a physicist and director of the Center for Bits and Atoms at Massachusetts Institute of Technology (MIT).

    The new wing consists of a system of tiny, strong, lightweight modules. The shape of the wing can be changed uniformly along its length using two small motors, which apply a twisting pressure to each wingtip. These wings are covered in “skins” of overlapping strips of flexible material resembling fish sizes. These strips move across each other as the wings alter, providing a smooth outer surface, the researchers explained.

    Wind-tunnel tests of these wings showed that they at least matched the aerodynamic properties of conventional wings, at about one-tenth the weight. Initial tests using remotely piloted aircrafts made with these wings have shown great promise, said Benjamin Jenett, a graduate student at the Center for Bits and Atoms at MIT.

    The new modular structures the scientists developed could be manufactured quickly in mass quantities and then installed by teams of small robots. These modular structures also can be disassembled more easily, making repairs simpler.

    “Still, the first aircraft built using this strategy will not be a passenger jet, ”Gershenfeld said. “Instead, the technology will likely first be tested on unmanned aircraft, leading to drones (无人机) that can fly for a long time, to help deliver internet access or medicine to remote villages and do some rescue works.”

    When many people are worried that there are no more heroes in the modern times, two university students who lost their lives to rescue drowning children have shown that heroes still exist (存在).

    According to the Inner Mongolia Morning Post. the tragedy (悲剧) occurred on the afternoon .December 14,2002 when three school students skating on a frozen lake in Qingcheng Park in Hohhot fell through the ice into the freezing water. More than 20 university students who happened to be near the Spot immediately went to the rescue of the children. Two children were quickly rescued, but the third died. The child's body was not found for three hours. Two of the rescuers, Liu Ye and had Longbiao, also died of cold and exhaustion. The body of Hao who took the lead in jumping into the lake was not found until the next day. A student who was unwilling to tell his name said he and his Classmates from the local college were taking photos at the lake. When they heard the children's criestor help, they went to the ice hole hand in hand to rescue the children. But the ice kept breaking, causing most of them to fall into the icy water.

    Local residents held mourning ceremonies (祭莫仪式) at the lake. Eight of the students were seriously affected by the freezing water and were being kept in hospital for further observation, but their lives were no longer in danger.

    The United States of America is faced with serious traffic problems. Too many cars travel on the freeways to and from the city. This heavy traffic causes delays and lots of pollution from cars that are using their engines but not moving anywhere. Many cars going nowhere is called a "traffic jam".

    While many cities in the United States have traffic problems, some of the worst are in Los Angeles, California, which is a big city with a large downtown area. One of the reasons why there is so much traffic is that few people use public transportation to get around.

    Experts say one possible solution to the traffic problems in Los Angeles would be to make people want to use the public transportation system of buses instead of their own cars. People say the buses should be made easier, faster, less costly and more dependable than driving a car.

    One suggestion is to reduce the cost of taking the bus. Also, Los Angeles could make the buses easier for people to use. The buses could travel to more places in the city. And there could be more special lanes on the freeways that only buses could drive in. These changes would make taking the bus faster and easier than driving a car.

    Other experts have said that the best way to ease traffic problems is to charge people money to drive on the freeways. These charges, or tolls, would be for the most crowded roads. The tolls would be in effect during the times of a day when most people drive to work and home. These times in the morning and late afternoon are called "rush hour". People would try to avoid driving on these roads, which would decrease the amount of traffic. Also, the money collected from these tolls could be used to improve the roads and public transportation system.

    Below you will find a profile of each gap year program. If there is a specific program you are interested in or a question you have regarding these programs, please feel free to contact them directly.

    Youth International

    Since 1997, Youth International has been providing many people with the most exciting and educational experience of their life. It is a learning program that combines international travel, inter-cultural exchange, home stays, volunteer community service work and outdoor adventures.

    Phone: 720-270-3323

    Carpe Diem Education

    Through volunteer service, travel and cultural exchange, students of Carpe Diem Education receive a personal insight into themselves and their cultures. We specialize in guiding summer and semester programs for high school students. Each course is carefully crafted to develop leadership and self-awareness within our students, who return home better prepared to be leaders in thought and action.

    Phone: 503-285-1800

    Center for Interim Programs

    Founded in 1980, Center for Interim Programs is the first independent gap-year organization in America. Based on students' interests and budget, our experienced teachers help make individual course choices including: low cost volunteer options, language programs, research trips, and so on. We are committed to helping students find more experiences of formal education and work.

    Phone: 413-585-0980

    EF Gap Year

    EF Gap Year offers students the ability to explore several countries where you will learn a language, volunteer for a good cause, gain international work experience. Choose between a 12-week semester or 26-week academic year. You can then personalize your program to meet your learning goals and interests by deciding where, when, and how you wish to study on your own. Our well-structured curriculum even allows you to place out of college-level classes and earn advanced credits toward graduation.

    Phone: 800-726-9746

Pacific Science Center Guide

◆Visit Pacific Science Centerˈs Store

Donˈt forget to stop by Pacific Science Centerˈs Store while you are here to pick up a wonderful science activity or souvenir to remember your visit. The store is located upstairs in Building 3 right next to the Laser Dome.

    ◆Hungry

Our exhibits will feed your mind but what about your body? Our café offers a complete menu of lunch and snack options, in addition to seasonal specials. The café is located upstairs in Building 1 and is open daily until one hour before Pacific Science Center closes.

    ◆Rental Information

    Lockers are available to store any belongings during your visit. The lockers are located in Building 1 near the Information Desk and in Building 3. Pushchairs and wheelchairs are available to rent at the Information Desk and Denny Way entrance. ID required.

◆Support Pacific Science Center

Since 1962, Pacific Science Center has been inspiring a passion for discovery and lifelong learning in science, math and technology. Today, Pacific Science Center serves more than 1.3million people a year and brings inquiry-based science education to classrooms and community events all over Washington State. Itˈs an amazing accomplishment and one we cannot achieve without generous support from individuals, corporations, and other social organizations. Visit pacific science center.org to find various ways you can support Pacific Science Center.