In this task, you're given an article and an answer. Your task is to generate the fill-in-the-blank question for this answer based on the given article. The blanks are always at the end of the question, and can be filled with more than one word or phrase.

[Q]: Article: On July 16th 1995, a new bookstore opened in the American city of Seattle. No one steps inside to buy anything. Yet, the store, if you could call it that, had sales last year of 7000 million dollars. Ten years ago, few people bought things over the Internet. Few thought it was safe. Amazon.com changed many people's minds. Ten years later, an estimated seven out of ten American adults have used a computer to buy something. Market researchers at ComScore Networks estimate online spending last year at 117,000 million dollars. That was for goods and travel services. The person who started Amazon, Jeff Bezos remains its leader. In the 1990s, he urged employees to help Amazon get big fast. Yet, Amazon invested in many similar businesses that failed. Amazon lost plenty of money. It did not make a profit until 2003. Its most recent profit and earnings report released last week was better than many market watchers had expected. Today people can buy not just books and music but also many other products through Amazon. It competes with eBay, which celebrates its 10th birthday in September. eBay calls itself "the world's online marketplace". It does not sell anything. Instead, it provides a way for others to sell goods and services. People who want to buy something make competing offers through online auctions. eBay has grown to include several other businesses. These include Paypal, a company that processes online payments. As online sellers grew, traditional stores saw the future. Today, stores from the smallest to the biggest sell on the Internet. These include the biggest of all, Wal-Mart.
Answer: one sells something while the other doesn't
[A]: Amazon.com and eBay are different in that _ .

[Q]: Article: "The days when the management in Western companies presented gold watches to long-serving employees to thank them for loyal service is now just a memory." says the Educational and Training Support Agency. This new development in the shape and movement of the workforce throughout Western businesses is partly a result of the way that layers of middle management are being removed, leaving more workers responsible for their own development. "Having workers take responsibility for their own development might be dramatic, but it is now the rule," says the Educational and Training Support Agency. "Today, not only are workers more mobile, they have to run to keep up with changes." says the Government-founded agency."It is no longer enough for a worker to gain a set of skills.Workers need the ability to react and get used to changes." This new system is also being pushed along by the way that industry is looking to its workers to renew their own skills.In the United States, some companies have contracts which repair their employees to show regularly how they have their skills up to date. Contrary to this traditions of the past, employers in the West are now looking for _ as recruits, people who can develop their own continuing education beyond the school and university system.At the same time.businesses are developing the capacity for workers to take up autonomous learning on site in workplace, so that the skills and abilities of all workers in a business continue to improve and increase."This.of course," says business theory."will also improve the productivity of the workers and therefore the profits of the company."
Answer: serving a company for life is rare now
[A]: The management in western companies no longer presents gold watches to their employees because _ .

[Q]: Article: Time Travel If you could travel in time, where would you go? Perhaps you would watch an original performance of a Shakespeare's play in Elizabethan England? What about hanging out with Laozi in the Spring and Autumn Period? Or maybe you'd voyage far ahead of the present day to see what the future holds. The possibility of time travel is indeed appealing. Stories exploring the subject have been around for hundreds of years. Perhaps the best known example is science fiction novel The Time Machine, which was written by H.G. Wells and published in 1895 for the first time. It was adapted into at least two feature films of the same name, as well as two television versions, and a large number of comic book adaptations. It is generally credited with the popularization of the concept of time travel using a vehicle that allows an operator to travel purposefully and selectively. The term "time machine", coined by Wells, is now universally used to refer to a vehicle transporting people into the far future. But could time travel actually be possible? Some scientists say yes, in theory. They propose using cracks in time and space called "wormholes", which could be used as shortcuts to other periods. Einstein's theory of relativity allows time travel in extreme circumstances. And British physicist Stephen Hawking says you could travel into the future with a really fast spaceship -- going at nearly the speed of light. Though building such a spaceship would of course be no simple task. Even if you could travel into the past, there is something called the "grandfather paradox". It asks what would happen if a time traveler were to go back in time and have his own grandfather killed for some reason, and therefore prevent himself from being born.If the time traveler wasn't born, how would he travel back in time? And would you really like to visit the future?In H.G.Wells' book, the main character travels into distant time where he arrives at a beach and is attacked by giant crabs. He then voyages 30 million years into the future where the only living thing is a black object with tentacles .If that's what's in store, maybe we are better just living in the present day after all.
Answer: suggest the possibility to invent the time machine
[A]:
Einstein's and Hawking's theories _ .