1．The people had no agriculture but, over thousands of years, had developed techniques and equipment to exploit their environment, basing their economy on fishing in streams and coastal waters that teemed with salmon, halibut, and other varieties of fish; gathering abalone, mussels, clams, and other shellfish from the rocky coastline; hunting land and sea mammals; and collecting wild plant foods.

2．The musicians within the orchestra’s ranks enrich their community immeasurably by ensuring that new generations of musicians, or simply music lovers, are given the kind of superior instruction that only an actively engaged, practicing musician can impart.

3．Since Canadian metropolitan areas have only one-quarter the number of kilometers of superhighways per capita as United States metropolitan areas – and at least as much resistance to constructing more – suburbanization of peoples and functions is less extensive north of the border than south.

4．They made available kinds of popular music heard previously only limited geographical areas or by specific ethnic and social groups – especially the blues, gospel songs, and jazz of African Americans and the traditional music of the southern Appalachian Mountains and other rural areas of the southern and western United States.

5．The development of the railroad and telegraph systems during the middle third of the nineteenth century led to significant improvements in the speed, volume, and regularity of shipments and communications, making possible a fundamental transformation in the production and distribution of goods.

6．Add to this the timidity with which unschooled artisans – originally trained as stonemasons, carpenters, or cabinetmakers – attacked the medium from which they were to make their images, and one understands more fully the development of sculpture made in the United States in the late eighteenth century.

7．Instead of trying to keep down the body temperature deep inside the body, which would involved the expenditure of water and energy, desert

mammals allow their temperatures to rise to what would normally be fever height, and temperatures as high as 46 degrees Celsius have been measured in Grant’s gazelles.

8．Solitary roosters shelter in dense vegetation or enter a cavity – horned larks dig holes in the ground and ptarmigan burrow into snow banks – but the effect of sheltering is magnified by several birds huddling together in the roots, as wrens, swifts, brown creepers, bluebirds, and anis do.

9．Each SMSA would contain at least (a) one central city with 50000 inhabitants or more or (b) two cities having shared boundaries and constituting, for general economic and social purposes, a single community with a combined population of at least 50000, the smaller of which must have a population of at least 15000.

10．The growing custom of regularly assembling from afar the representatives of all kinds of groups, not only for political conventions, but also for commercial, professional, learned, and vocational ones… in turn supported the multiplying hotels.

11．Two species of these finches, named for the way the upper and lower parts of their bills cross, rather than meet in the middle, reside in the evergreen forests of North American and feed on the seeds held within the cones of coniferous trees.

12．The beginning of a major change was foreshadowed in the later 1860’s, when the Union Pacific Railroad at last began to build westward from the Central Plains city of Omaha to meet the Central Pacific Railroad advancing eastward from California through the formidable barrier of the Sierra Nevada.

13．The argument that humans, even in prehistoric, had some number sense, at least to the extent of recognizing the concept of more and less when some objects were added to or taken away from a small group, seems fair, for studies have shown that some animal possess such a sense.

14．A useful definition of an air pollutant is a compound added directly or indirectly by humans to the atmosphere in such quantities as to affect humans, animals, vegetation, or materials adversely.

15．The tight arrangement enabled the Mandans to protect themselves more easily from the attacks of others who might seek to obtain some of the food these highly capable farmers stored from one year to next.

16．No other set of colonists took so seriously one expression of the period, “Leisure is time for doing something useful,” in the countryside farmers therefore relieved the burden of the daily routine with such double-purpose relaxations as hunting, fishing, and trapping.

17．Life on Earth has continually been in flux as slow physical and chemical changes have occurred on Earth, but life needs time to adapt – time for migration and genetic adaptation within existing species and time for the proliferation of new genetic material and new species that may be able to survive in environments.

18．Some fossil bones have all the interstitial spaces filled with foreign minerals, including the marrow cavity, if there is one, while others have taken up but little from their surroundings.

19．By 1776 the fine art of painting as it had developed in western Europe up to this time had been introduced into the American colonies through books and paints, European visitors and immigrants, and traveling colonists who brought back copies (and a few originals) of old master paintings and acquaintance with European art institutions.

20．The terminology by which artists were described at the time suggests their status: “limner” was usually applied to the anonymous portrait painter up to the 1760’s: “painter” characterized anyone who could paint a flat surface.

21．A few art collectors James Bowdoin III of Boston, William Byrd of Virginia, and the Aliens and Hamiltons of Philadelphia introduced European art traditions to those colonists privileged to visit their galleries, especially aspiring artists,

22．The achievements of the colonial artists, particularly those of Copley, West, and Peale, lent credence to the boast that the new nation was capable of encouraging genius and that political liberty was congenial to the development of taste – a necessary step before art could assume an important role in the new republic.

23．In its grand and impressive terminals and stations, architects recreated historic Roman temples and public baths, French chateaus and Italian bell towers – edifices that people used as stages for many of everyday life’s high emotions: meeting and parting, waiting and worrying, planning new starts or coming home.

24．Moreover, in addition to its being a transportation pathway equipped with a mammoth physical plant of tracks signals, crossings, bridges, and junctions, plus telegraph and telephone lines the railroad nurtured factory complexes, coat piles, warehouses, and generating stations, forming along its right-of-way what has aptly been called “the metropolitan corridor” of the American landscape.

25．It was in the cities that the elements that can be associated with modern capitalism first appeared – the use of money and commercial paper in place of barter, open competition in place of social deference and hierarchy, with an attendant rise in social disorder, and the appearance of factories using coal or water power in place of independent craftspeople working with hand tools.

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