[简答题]文献的涵义是什么？

Exercise, everyone advises! But immediately, when you try, you run into trouble. (46)There is so much contradictory, sometimes incorrect advice about exercising that you become confused. Test yourself on the following true false quiz. It will tell you what you need to know.
1. The best way to reduce the mid-section is to do abdominal exercise.
False. Many people believe that when specific muscles are exercised, the fatty tissues in the immediate area are "burned up." (47)The truth-is that exercise burns fat from all over the body and not from one specific area, regardless of the type of exercise. Of course, if you reduce the fat throughout your body, you will certainly see results around your waistline too!
2. To maintain an adequate level of physical fitness, you need to exercise only twice a week.
False. Studies conducted by NASA, the National Aeronautics and Space Administration, show that unexercised muscles lose their s

Black people were first taken to North America as slaves in the seventeenth century. Sold by Arab or Mrican slave-traders in West Mrica, they were on the tobacco, sugar and cotton plantations.
Towards the end of the eighteenth century, more and more people began to condemn (谴责) slavery, but it was not until after the bitter Civil war-between the Northern and Southern states of America that is was abolished there. In 1865 the 13th Amendment to the Constitution gave blacks the right to live and work where they liked. Then ,in 1867, came further legislation (立法)guaranteeing citizenship and other civil rights.
However, there were setbacks almost immediately. The Supreme Court declared the civil rights legislation of 1867 unconstitutional and a number of new segregation (种族隔离)laws were enacted. Consequently ,as more and more blacks deserted the rural areas in search of work in the cities, they found themselves forced to .live in areas with the worst housing and
A. They came to North America for more lands and more working opportunities.
B. They came from Asian and Europe.
C. They were shipped to the North America by some slave-traders.
D. They got good treatment when they were ill.