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.
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Question: Article: In 1901, H.G. Wells, an English writer, wrote a book describing a trip to the moon. When the explorers landed on the moon, they discovered that the moon was full of underground cities. They expressed their surprise to the "moon people" they met. In turn, the "moon people" expressed their surprise. "Why," they asked, "are you traveling to outer space when you don't even use your inner space?" H.G. Wells could only imagine travel to the moon. In 1969, human beings really did land on the moon. People today know that there are no underground cities on the moon. However, the question that the "moon people" asked is still an interesting one. A growing number of scientists are seriously thinking about it. Underground systems are already in place. Many cities have underground car parks. In some cities, such as Tokyo, Seoul and Montreal, there are large underground shopping areas. The "Chunnel", a tunnel connecting England and France, is now complete. But what about underground cities? Japan's Taisei Corporation is designing a network of underground systems, called "Alice Cities." The designers imagine using surface space for public parks and using underground space for flats, offices, shopping, and so on. A solar dome would cover the whole city. Supporters of underground development say that building down rather than building up is a good way to use the earth's space. The surface, they say, can be used for farms, parks, gardens, and wilderness. H.G. Wells' "moon people" would agree. Would you?
Answer: lived in so many underground cities

Answer: The explorers in H. G. Wells' story were surprised to find that the "moon people" _ .

Question: Article: When we see well, we do not think about our eyes very often. It is only when we cannot see perfectly that we realize how important our eyes are. People who are near-sighted can only see things that are very close to their eyes. Everything else seems blurry (unclear). Many people who do a lot of work, such as writing, reading and sewing become near--sighted. People who are far-sighted _ from just the opposite problem. They can see things that are far away, but they have difficulty in reading a book unless they hold it at arm's length. If they want to do much reading, they must get glasses, too. Other people do not see clearly because their eyes are not exactly the right shape. They have what is called astigmatism . This, too, can be corrected by glasses. Some people's eyes become cloudy because of cataracts . Long ago these people often became blind. Now, however, it is possible to operate on the cataracts and remove them. Having two good eyes is important for judging distances. Each eye sees things from a slightly different angle. To prove this to yourself, look at an object out of one eye; then look at the same object out of your other eye. You will find the object's relation to the background and other things around it has changed. The difference between these two different eye views helps us to judge how far away an object is. People who have only one eye cannot judge distance as people with two eyes.
Answer: only when we realize how important our eyes are

Answer: We should take good care of our eyes _ .

Question: Article: One day last September, as Britney Spears was about to board a flight to Los Angeles from prefix = st1 /London, a blue bottle fell out of her purse. She quickly put it back in, but not before the camera recorded the event. Neither Spears nor her spokesman was willing to comment on the contents of the bottle, but the next morning London's Daily Express published a page of pictures under the headline "EXCLUSIVE: POP PRINCESS SPOTTED AT AIRPORT WITH POT OF SLIMMING TABLETS." Spears was apparently carrying Zantrex-3, one of the most popular weight-loss pills now sold in theUnited States. The pill, which is sold at about fifty dollars for a month's supply, contains a huge amount of caffeine, some green tea, and three common South American herbs that also act as stimulants . It hit the U.S.market last March and has had _ . Millions of bottles have been sold, and during the Christmas season it was displayed in the windows of the nation's largest chain of vitamin shops, G.N.C. (It is so highly sought after that many of the stores keep it in locked counters.) Zantrex-3 is also sold at CVS, Rite _ Aid, Wal-Mart, and other chains, and over the telephone and on the Internet. If you type "Zantrex" into Google, more than a hundred thousand pieces of information about it will appear. At any moment, there are scores of people sell it on eBay. Perhaps the most interesting thing aboutthe success story of Zantrex-3, however, is that _ is far from unique. There are hundreds of similar products on the market today, and they are bought by millions of Americans. And though Zantrex's producer makes some exciting statements ("the most advanced weight control compound period"), so do the people who sell Stacker 2 and Anorex along with those who sell Carb Eliminator and Fat Eliminator. Almost all of these compounds suggest that they can help people lose weight and regain lost energy, and often without diet, exercise, or any other effort.
Answer: singer

Answer:
Britney Spears is a / an _ .