2019 年 06 月大学英语六级考试真题（第 3 套）

Steel is valued for its reliability, but not when it gets cold. Most forms of steel __26__ become brittle (脆的) at temperatures below about -25℃ unless they are mixed with other metals. Now, though, a novel type of steel has been developed that resists __27__ at much lower temperatures, while retaining its strength and toughness - without the need for expensive __28__.

Steel's fragility at low temperatures first became a major concern during the Second World War. After German U-boats torpedoed (用鱼雷攻击) numerous British ships, a 2700-strong fleet of cheap-and-cheerful "Liberty ships" was introduced to replace the lost vessels, providing a lifeline for the __29__ British. But the steel shells of hundreds of the ships __30__ in the icy north Atlantic, and 12 broke in half and sank.

Brittleness remains a problem when building steel structures in cold conditions, such as oil rigs in the Arctic. So scientists have __31__ to find a solution by mixing it with expensive metals such as nickel.

Yuuji Kimura and colleagues in Japan tried a more physical __32__. Rather than adding other metals, they developed a complex mechanical process involving repeated heating and very severe mechanical deformation, known as tempforming.

The resulting steel appears to achieve a combination of strength and toughness that is __33__ to that of modern steels that are very rich in alloy content and, therefore, very expensive.

Kimura's team intends to use its tempformed steel to make ultra-high strength parts, such as bolts. They hope to reduce both the number of __34__ needed in a construction job and their weight by replacing solid supports with __35__ tubes, for example. This could reduce the amount of steel needed to make everything from automobiles to buildings and bridges.

When I re-entered the full-time workforce a few years ago after a decade of solitary self-employment, there was one thing I was looking forward to the most: the opportunity to have work friends once again. It wasn't until I entered the corporate world that I realized, for me at least, being friends with colleagues didn't emerge as a priority at all. This is surprising when you consider the prevailing emphasis by scholars and trainers and managers on the importance of cultivating close interpersonal relationships at work. So much research has explored the way in which collegial (同事的) ties can help overcome a range of workplace issues affecting productivity and the quality of work output such as team-based conflict, jealousy, undermining, anger, and more.

Perhaps my expectations of lunches, water-cooler gossip and caring, deep-and-meaningful conversations were a legacy of the last time I was in that kind of office environment. Whereas now, as I near the end of my fourth decade, I realize work can be fully functional and entirely fulfilling without needing to be best mates with the people sitting next to you.

In an academic analysis just published in the profoundly-respected Journal of Management, researchers have looked at the concept of "indifferent relationships". It's a simple term that encapsulates (概括) the fact that relationships at work can reasonably be non-intimate, inconsequential, unimportant and even, dare I say it, disposable or substitutable.

Indifferent relationships are neither positive nor negative. The limited research conducted thus far indicates they're especially dominant among those who value independence over cooperation, and harmony over confrontation. Indifference is also the preferred option among those who are socially lazy. Maintaining relationships over the long term takes effort. For some of us, too much effort.

As noted above, indifferent relationships may not always be the most helpful approach in resolving some of the issues that pop up at work. But there are nonetheless several empirically proven benefits. One of those is efficiency. Less time chatting and socializing means more time working and churning (产出).

The other is self-esteem. As human beings, we're primed to compare ourselves to each other in what is an anxiety-inducing phenomenon. Apparently, we look down on acquaintances more so than friends. Since the former is most common among those inclined towards indifferent relationships, their predominance can bolster individuals' sense of self-worth.

Ego aside, a third advantage is that the emotional neutrality of indifferent relationships has been found to enhance critical evaluation, to strengthen one's focus on task resolution, and to gain greater access to valuable information. None of that might be as fun as after-work socializing but, hey, I'll take it anyway.

In a few decades, artificial intelligence (AI) will surpass many of the abilities that we believe make us special. This is a grand challenge for our age and it may require an "irrational" response.

One of the most significant pieces of news from the US in early 2017 was the efforts of Google to make autonomous driving a reality. According to a report, Google's self-driving cars clocked 1,023,330 km, and required human intervention 124 times. That is one intervention about every 8,047 km of autonomous driving. But even more impressive is the progress in just a single year: human interventions fell from 0.8 times per thousand miles to 0.2, a 400% improvement. With such progress, Google's cars will easily surpass my own driving ability later this year.

Driving once seemed to be a very human skill. But we said that about chess, too. Then a computer beat the human world champion, repeatedly. The board game Go (围棋) took over from chess as a new test for human thinking in 2016, when a computer beat one of the world's leading professional Go players. With computers conquering what used to be deeply human tasks, what will it mean in the future to be human? I worry about my six-year-old son. What will his place be in a world where machines beat us in one area after another? He'll never calculate faster, never drive better, or even fly more safely. Actually, it all comes down to a fairly simple question: What's so special about us? It can't be skills like arithmetic, which machines already excel in. So far, machines have a pretty hard time emulating creativity, arbitrary enough not to be predicted by a computer, and yet more than simple randomness.

Perhaps, if we continue to improve information-processing machines, we'll soon have helpful rational assistants. So we must aim to complement the rationality of the machine, rather than to compete with it. If I'm right, we should foster a creative spirit because a dose of illogical creativity will complement the rationality of the machine. Unfortunately, however, our education system has not caught up to the approaching reality. Indeed, our schools and universities are structured to mould pupils to be mostly obedient servants of rationality, and to develop outdated skills in interacting with outdated machines. We need to help our children learn how to best work with smart computers to improve human decision-making. But most of all we need to keep the long-term perspective in mind: that even if computers will outsmart us, we can still be the most creative. Because if we aren't, we won't be providing much value in future ecosystems, and that may put in question the foundation for our existence.