Input: Middle Ages
Society throughout Europe was disturbed by the dislocations caused by the Black Death. Lands that had been marginally productive were abandoned, as the survivors were able to acquire more fertile areas. Although serfdom declined in Western Europe it became more common in Eastern Europe, as landlords imposed it on those of their tenants who had previously been free. Most peasants in Western Europe managed to change the work they had previously owed to their landlords into cash rents. The percentage of serfs amongst the peasantry declined from a high of 90 to closer to 50 per cent by the end of the period. Landlords also became more conscious of common interests with other landholders, and they joined together to extort privileges from their governments. Partly at the urging of landlords, governments attempted to legislate a return to the economic conditions that existed before the Black Death. Non-clergy became increasingly literate, and urban populations began to imitate the nobility's interest in chivalry.

In what part of Europe did serfdom increase in this period?
Output: Eastern

Input: Korean War
The on-again, off-again armistice negotiations continued for two years, first at Kaesong, on the border between North and South Korea, and then at the neighbouring village of Panmunjom. A major, problematic negotiation point was prisoner of war (POW) repatriation. The PVA, KPA, and UN Command could not agree on a system of repatriation because many PVA and KPA soldiers refused to be repatriated back to the north, which was unacceptable to the Chinese and North Koreans. In the final armistice agreement, signed on 27 July 1953, a Neutral Nations Repatriation Commission, under the chairman Indian General K. S. Thimayya, was set up to handle the matter.

How long did the armistice talks last?
Output: two years

Input: Adult contemporary music
The consolidation of the "hot AC" format contrasted with the near-demise of most other AC formats: Beginning with the 2005-2007 economic downturn and eventual recession most stations went for the more chart-based CHR, along with the top 40, urban and even Latino formats. Diminishing physical record sales also proved a major blow to the AC genre.

Along with the recession, what broad economic trend marked the decline of adult contemporary radio stations?
Output: the 2005-2007 economic downturn

Input: United States Army
The American Civil War was the costliest war for the U.S. in terms of casualties. After most slave states, located in the southern U.S., formed the Confederate States, C.S. troops led by former U.S. Army officers, mobilized a very large fraction of Southern white manpower. Forces of the United States (the "Union" or "the North") formed the Union Army consisting of a small body of regular army units and a large body of volunteer units raised from every state, north and south, except South Carolina.[citation needed]

What were the U.S. forces referred to as?
Output:
the "Union" or "the North"