High wages and restrictive work practices are said to have created new nonunion competition.

单项选择题Among the men and women who reshaped the American working class during the early 1900s, there were many who were not members of labor unions.

单项选择题The most important result of the Lewis and Clark expedition was that it enabled the United States to claim the Oregon region.

单项选择题The cylindrical shape of a cactus reduces moisture loss.

单项选择题By 1900, many municipalities had begun to restrict the use of automobiles in order to en- sure pedestrian safety.

单项选择题Over thirty cities around the world boast more than five million residents.