Only under special circumstances （ ） to take make-up tests.
Airplane and television are among the（ ）of science.
Since everyone would like to find an apartment near the University, there are very few（ ）apartments in the area.
Real-time web search—which scours only the latest updates to services like Twitter—is currently generating quite a buzz because it can provide a glimpse of what people around the world are thinking or doing at any given moment. Interest in this kind of search is so great that, according to recent leaks, Google is considering buying Twitter.The latest research from the interact search giant, though, suggests that real-time results could be even more powerful—they may reveal the future as well as the present.Google researchers Hyunyoung Choi and Hal Varian combined data from Google Trends on the popularity of different search terms with models used by economists to predict trends in areas such as travel and home sales. The result? Better forecasts in almost every case. It works because searches reveal something about people’s intentions. Google has demonstrated before that search data can predict flu outbreaks, and last week World Bank economist Erik Feyen said he could cut errors in a model that forecasts lending to the private sector by 15% using Google search data.But real-time results could have even more predictive power: knowing what people are actually doing, not just thinking, at a particular instant gives a strong hint of the future consequences.Johan Bollen of Los Alamos National Laboratory and Alberto Pepe of the University of California, Los Angeles, applied a mood rating system to the text from over 10,000 Future Me emails sent in 2006 to gauge people’s hopes, fears and predictions for the future. They found that emails directed at 2007 to 2012 were significantly more depressed in tone than messages aimed at the subsequent six years. Could they have predicted the world’s current economic slump?Without more data, that is no more than an intriguing possibility. So Bollen plans to look at more Future Me emails, as well as Twitter messages, to search for mood swings that foreshadow other economic changes. If he finds any such links, the same sources might be used to try and predict future economic fluctuations.So will our online footsteps become a central part of economic forecasting? We’ll have to wait and see—or perhaps do a quick web search.1.What is “real-time” web search like Twitter?2.What is the result of research established by Google researchers Hyunyoung Choi and Hal Varian?3.What can we infer from Para. 5?4.What's the meaning of “Without more data, that is no more than an intriguing possibility.”？5.What's the attitude of author to real-time search?
The mere fact（ ）most people believe a nuclear war would be mad does not mean that it will not occur.
The migratory birds use the same nests year after year,（ ） new material each time.