2.According to the article, the technology of CRISPR 　　　.

　A.is very safe because it only cuts the DNA it is looking for

　B.is banned in 42 countries and restricted in many others

　C.could cause parents to make unwise choices for their children

　D.could help us discover the link between DNA and the qualities it gives people

3.It can be concluded from the article that CRISPR 　　　.

　A.can be helpful in the treatment of cancer and HIV

　B.allows scientists to edit the genomes for the first time

　C.is a technology that uses an enzyme to work on RNA and DNA

　D.has proven to be the most effective way to protect children against diseases

4.What is the author's attitude toward CRISPR?

　A.Supportive. B.Worried.

　C.Negative. D.Objective.

答案

1.D　2.C　3.A　4.D　

　　Before 1815 manufacturing in the United States had been done in homes or shops by skilled artisans (工匠).As master craft workers, they passed on the knowledge of their trades to apprentices and journeymen. In addition,women often worked in their homes part-time, making finished articles from raw material supplied by merchant capitalists. After 1815 this older form of producing began to give way to factories with machinery tended by unskilled or semiskilled laborers. Cheap transportation networks, the rise of cities, and the availability of capital and credit all stimulated (刺激)the shift to factory production.

The factory changed that. Goods produced by factories were not as finished or elegant as those done by hand, and pride in craftsmanship (工艺)gave way to the pressure to increase rates of productivity. The new methods of doing business involved a new and stricter sense of time. Factory life necessitated a more rigid schedule, where work began at the sound of a bell and workers kept machines going at a constant pace.