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The abbey's two western towers were built between 1722 and 1745 by Nicholas Hawksmoor, constructed from Portland stone to an early example of a Gothic Revival design. Purbeck marble was used for the walls and the floors of Westminster Abbey, even though the various tombstones are made of different types of marble. Further rebuilding and restoration occurred in the 19th century under Sir George Gilbert Scott.
Who built the western towers of the abbey?
A: Nicholas Hawksmoor

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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.
The use of a printed score and the performance of very complex instrumental works are characteristics of what?
A: classical music

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In 1983 the historic old town in the centre of Bern became a UNESCO World Heritage Site. Bern is ranked among the world’s top ten cities for the best quality of life (2010).
Where is the UNESCO World Heritage Site?
A: centre of Bern

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Poetry is a form of literary art which uses aesthetic and rhythmic qualities of language to evoke meanings in addition to, or in place of, prosaic ostensible meaning. Poetry has traditionally been distinguished from prose by its being set in verse;[a] prose is cast in sentences, poetry in lines; the syntax of prose is dictated by meaning, whereas that of poetry is held across metre or the visual aspects of the poem. Prior to the nineteenth century, poetry was commonly understood to be something set in metrical lines; accordingly, in 1658 a definition of poetry is "any kind of subject consisting of Rythm or Verses". Possibly as a result of Aristotle's influence (his Poetics), "poetry" before the nineteenth century was usually less a technical designation for verse than a normative category of fictive or rhetorical art. As a form it may pre-date literacy, with the earliest works being composed within and sustained by an oral tradition; hence it constitutes the earliest example of literature.
The structure of poetry may have existed before what?
A:
literacy