Input: Classical music
Given the wide range of styles in classical music, from Medieval plainchant sung by monks to Classical and Romantic symphonies for orchestra from the 1700s and 1800s to avant-garde atonal compositions for solo piano from the 1900s, it is difficult to list characteristics that can be attributed to all works of that type. However, there are characteristics that classical music contains that few or no other genres of music contain, such as the use of a printed score and the performance of very complex instrumental works (e.g., the fugue). As well, although the symphony did not exist through the entire classical music period, from the mid-1700s to the 2000s the symphony ensemble—and the works written for it—have become a defining feature of classical music.

What has become a defining feature of classical music?
Output: the symphony ensemble

Input: Phonology
Phonology is often distinguished from phonetics. While phonetics concerns the physical production, acoustic transmission and perception of the sounds of speech, phonology describes the way sounds function within a given language or across languages to encode meaning. For many linguists, phonetics belongs to descriptive linguistics, and phonology to theoretical linguistics, although establishing the phonological system of a language is necessarily an application of theoretical principles to analysis of phonetic evidence. Note that this distinction was not always made, particularly before the development of the modern concept of the phoneme in the mid 20th century. Some subfields of modern phonology have a crossover with phonetics in descriptive disciplines such as psycholinguistics and speech perception, resulting in specific areas like articulatory phonology or laboratory phonology.

When was the phonome's modern concept developed?
Output: mid 20th century

Input: Kievan Rus%27
The new Kievan state prospered due to its abundant supply of furs, beeswax, honey, and slaves for export, and because it controlled three main trade routes of Eastern Europe. In the north, Novgorod served as a commercial link between the Baltic Sea and the Volga trade route to the lands of the Volga Bulgars, the Khazars, and across the Caspian Sea as far as Baghdad, providing access to markets and products from Central Asia and the Middle East. Trade from the Baltic also moved south on a network of rivers and short portages along the Dnieper known as the "route from the Varangians to the Greeks," continuing to the Black Sea and on to Constantinople. Kiev was a central outpost along the Dnieper route and a hub with the east-west overland trade route between the Khazars and the Germanic lands of Central Europe. These commercial connections enriched Rus' merchants and princes, funding military forces and the construction of churches, palaces, fortifications, and further towns. Demand for luxury goods fostered production of expensive jewelry and religious wares, allowing their export, and an advanced credit and money-lending system may have also been in place.

Which route was a central post in Kiev?
Output: Dnieper route

Input: Circadian rhythm
The earliest recorded account of a circadian process dates from the 4th century B.C.E., when Androsthenes, a ship captain serving under Alexander the Great, described diurnal leaf movements of the tamarind tree. The observation of a circadian or diurnal process in humans is mentioned in Chinese medical texts dated to around the 13th century, including the Noon and Midnight Manual and the Mnemonic Rhyme to Aid in the Selection of Acu-points According to the Diurnal Cycle, the Day of the Month and the Season of the Year.

What tree leaves did Androsthenes describe?
Output:
tamarind