【推荐1】While it may seem that a cab driver has only one responsibility—to drive customers to and from certain destinations, this is not the case. Instead, a cab driver must be ready to take on a number of different tasks.     1     Taxis have been around in various forms for many centuries, and the many duties of a cab driver increase as time goes on.    2     Not only do cab drivers have to pick up all kinds of people, but many of them have to interact with their customers. Frequently, cab drivers are hired by tourists or business people for an entire day, and this can mean making unavoidable contact with different people with different personalities.

Taxi drivers must also be able to operate different types of vehicles.     3    The vehicles have ramps (斜面) that can be raised and lowered. This type of vehicle requires a special license that most cab drivers must get before obtaining   a position as a taxi driver.

Generally, cab drivers are not required to repair vehicles.     4     For example, almost all taxi drivers know how to change tires（轮胎）, lights, and other small vehicle parts. Many drivers are also responsible for checking the taxi on a regular basis.

Perhaps the most important task that a cab driver must be aware of is how to charge a customer for each trip. While the prices of some trips have been predetermined（商定）, such as airport fares, other trips must be calculated using taximeters（计价器） and fee charts.     5    

【推荐1】For most city people, the elevator is an unremarkable machine that inspires none of the enthusiasm or interest that Americans afford trains, jets, and even bicycles. Dr. Christopher Wilk is a member of a small group of elevator experts who consider this a misunderstanding. Without the elevator, they point out, there could be no downtown skyscrapers or tall buildings, and city life as we know it would be impossible. In that sense, they argue, the elevator’s role in American history has been no less significant than that of cars. In fact, according to Wilk, the car and the elevator have been locked in a “secret war” for over a century, with cars making it possible for people to spread horizontally(水平地), and elevators pushing them toward life in close groups of towering vertical (垂直的) columns.

If we tend to ignore the significance of elevators, it might be because riding in them tends to be such a brief, boring, and even awkward experience one that can involve unexpectedly meeting people with whom we have nothing in common, and an unpleasant awareness of the fact that we’re hanging from a cable in a long passage.

In a new book, Lifted, German journalist and cultural studies professor Andreas Bernard directed all his attention to this experience, studying the origins of elevator and its relationship to humankind and finding that riding in an elevator has never been a totally comfortable experience. “After 150 years, we are still not used to it, ”Bernard said. “We still have not exactly learned to cope with the mixture of closeness and displeasure.” That mixture, according to Bernard, sets the elevator ride apart from just about every other situation we find ourselves in as we go about our lives.

Today, as the world’s urban population explodes, and cities become more crowded, taller, and more crowded, America’s total number of elevators—900,000 at last count, according to Elevator World magazine’s “2012 Vertical Transportation Industry”—are a force that’s becoming more important than ever. And for the people who really, really love them, it seems like high time that we looked seriously at just what kind of force they are.

【推荐3】Improvements to energy efficiency, such as LED lights, are seen by many authorities as a top priority for cutting carbon emissions. Yet a growing body of research suggests that a rebound effect could wipe out more than half of the savings from energy efficiency improvements, making the goals of the Paris Agreement on climate change even harder to hit.

A team led by Paul Brockway at the University of Leeds, UK, looked at the existing 33 studies on the impact of the rebound effect. First comes the direct rebound: for instance, when someone buys a more efficient car, they may take advantage of that by driving it further. Then comes the indirect rebound: fuel savings leave the owner with more money to spend elsewhere in the economy, consuming energy.

Although the 33 studies used different methods to model the rebound effect, they produced very consistent estimates of its impact, leading the team to conclude that the effect wipes out, on average, 63 percent of the anticipated energy savings.

“We’re not saying energy efficiency doesn’t work. What we’re saying is rebound needs to be taken more seriously,” says Brockway.

The idea that increased efficiency may not deliver the hoped-for savings dates back to the Jevons paradox(悖论), named after the economist William Stanley Jevons, who, in 1865, observed that more efficient coal use led to more demand for coal.

If the rebound effect does prove to be as big as suggested, it means future global energy demand will be higher than expected and the world will need far more wind and solar power and carbon-capture technology than is currently being planned for.

But that doesn’t mean nothing can be done to limit the rebound effect. One answer is to double down on energy efficiency and do twice as much to achieve the same effect.