2 . Self-driving vehicles will rely on cameras，sensors and artificial intelligence (Al) 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 researches show that cars will need to be able to chat and operate on the road，although the technical challenges are considerable.

Applications for vehicle-to-vehicle communication range from vehicles driving together in a row，to 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 meters away.vehicles could exchange messages with one another or receive information from roadside units (RSUs) about nearby incidents or dangerous road conditions through 4 G network.A high level of Al 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 in the light of 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 potential risks，or a vehicle could decide to drop someone of earlier due to messages received，a foreseen crowding ahead.

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

7 . I was desperately nervous about becoming car-free. But eight months ago our car was hit by a passing vehicle and it was destroyed. No problem, I thought: we’ll buy another. But the insurance payout didn’t even begin to cover the costs of buying a new car—I worked out that, with the loan (贷款) we’d need plus petrol, insurance, parking permits and tax, we would make a payment as much as £600 a month.

And that’s when I had my fancy idea. Why not just give up having a car at all？I live in London. We have a railway station behind our house, a tube station 10 minutes’ walk away, and a bus stop at the end of the street. A new car club had just opened in our area, and one of its shiny little red Peugeots was parked nearby. If any family in Britain could live without a car, I reasoned, then surely we were that family.

But my new car-free idea, sadly, wasn’t shared by my family. My teenage daughters were horrified. What would their friends think about our family being “too poor to afford a car”？(I wasn’t that bothered what they thought, and I suggested the girls should take the same approach.)

My friends, too, were astonished at our plan. What would happen if someone got seriously ill overnight and needed to go to hospital？(an ambulance) How would the children get to and from their many events？(buses and trains) People smiled as though this was another of my mad ideas, before saying they were sure I’d soon realize that a car was a necessity.

Eight months on, I wonder whether we’ll ever own a car again. The idea that you “have to” own a car, especially if you live in a city, is all in the mind. I live—and many other citizens do too—in a place that has never been better served by public transport, and yet car ownership has never been higher. We worry about rising car costs, but we’d be better off asking something much more basic: do I really need a car？Certainly the answer is no, and I’m a lot richer because I dared to ask the question.

Ten years ago, people bought electric vehicles (EVs) to reduce their carbon footprint.     1     the limited range and high price made EVs something of a rare sight on roads. A lot can change in a decade. Advances in battery technology     2     (mean) electric cars now travel much further on a single charge. Government grants (补贴) serve to draw buyers away from gasoline-powered cars. The change will have a huge impact     3     life. Roads will become far     4     (quiet) and pollution levels will be reduced quickly, potentially leading to improved quality of life.

In most big cities, it is easier to hire a taxi at a moment’s notice when the weather is good. But when it’s raining, people have a much harder time     1    (find) one. One obvious reason is that many people who walk short distances during good weather prefer to take a taxi in the rain.     2    , taxis tend to be more fully occupied on rainy days. Besides, the supply of available taxis is also smaller because taxi drivers can     3     (easy) reach the target fares and go home early.

10 . Is traffic a big problem where you live? Increased cycling may be the answer. Where are the best places to live and cycle? A new report lists the best bike-friendly cities around the world.

Top of the list is Amsterdam, the bike capital of the world. An incredible 40% of all traffic movements are by bicycle. There’s an extensive network of safe, fast and comfortable cycle routes. Copenhagen, the city of bikes, is a city where 32% of workers cycle to work because it’s fast and easy. Berlin is another European city that’s great for cycling. The city has about 80 kilometers of bike lanes, and 50 kilometers of pavement paths. Cycling accounts for 12% of total street traffic.

Barcelona has been praised for its cycle service “Bicing”. This was introduced in March 2007. It’s a bicycle service that allows users to take bicycles from any of the 100 stations spread around the city. Later, they can leave them at any other bike station inside the urban area of the city. The city has created a “green ring” that surrounds the city area of Barcelona with a bike path. There are 3,250 parking spaces for bikes at street level at present. Barcelona City is also building a new underground car park for bicycles.

The UK has its cycle-friendly cities too. Bristol is the birthplace of “Sustrans” —the cycle-route charity which was formed 30 years ago. One of their projects was turning an old rail line between Bristol and Bath into a bike route. Other bike-friendly cities in the UK include Cambridge and York Cambridge is an old city but has still managed to build good cycle infrastructure (基础设施), and cyclists are considered at every stage of any new developments.

Bicycle is a most popular means of transportation in China. Nowadays, riding a bicycle is also a good way to support low-carbon living. Beijing can be one of the best bike-friendly cities in China. There are many riding routes in Beijing for outdoor-lovers to explore. Cyclists can get close enough to experience the history and culture of Beijing, including the Forbidden City, Drum Tower, the Water Cube, the Bird’s Nest, Hutong etc.