A、To pursue a better life. B、To seek for freedom. C、To search for gold. D、To do business. D

Between 1815 and 1915, more than 30 million immigrants arrived in the United States. These were people from other countries who came to make the United States their home.
    Immigrants came for many reasons. Some were driven away from home by hardships such as hunger, poverty, overpopulation, or political and religious troubles. Some were attracted to the United States by the promise of a better life. They had heard stories about cheap land, high wages, and even about streets paved with gold. Some came because of the promise of greater freedom in this new nation.
    There were two periods when immigrants came in greater numbers than usual. Between 1815 and 1860, large numbers of people came from northern Europe. The largest groups were Irish and Germans. Some Asians, mostly Chinese, also came during this time.
    Most Irish immigrants landed in Northern port cities such as Boston, New York, and Philadelphia. They did not have enough money to buy farms. Most settled in the poorest areas of these cities. Irish people got the worst jobs and lowest pay.
    The gold rush of 1849 brought many Chinese to California. In 1850 alone, 25000 young Chinese arrived in California. The Chinese worked in the gold mines. They helped build the first railroad to cross the nation, which was finished in 1869.
    The second great wave of immigrants came mostly from eastern and southern Europe between 1890 and 1910. Giant factories and businesses in the United States needed more and more workers. After 1900, as many as 15000 people would arrive in one day.
    Life in the United States was very difficult for almost all the new immigrants. And yet, many found some of their dreams coming true.