答案　1. B　2. C　3. D　4. D　5. D

Ⅱ. 课文语法填空

　　Cloning is a way of 1. ________(make)an exact copy of another animal or plant. 2. ________has two major uses. One is 3. ________gardeners use it to produce commercial quantities of plants. The other is that it is valuable for research on new species and for medical research on animals. 4. ________，the process of cloning is difficult5. ________(undertake)．

　　Many attempts to clone mammals failed. The first successful clone，Dolly the sheep，made the whole6. ________(science)world follow its process，though it had7. ________problems than the normal sheep. On the other hand，Dolly's appearance8. ________(raise)a storm of objections and had a great impact9. ________the media and public10. ________(imagine)．Different people have different opinions on it. However，scientists still wonder whether cloning will help or harm us and where it is leading us.

答案　1. making　2. It　3. that　4. However　5. to undertake　6. scientific

7．more　8. raised　9. on　10. imagination

【话题语篇导读】

What is cloning?

Cloning is a process used to create an exact copy of a mammal by using the complete genetic material of a regular body cell. Different from the common propagation，cloning needs only one cell and without sex. In 1997，the great news shocked the whole world that the British scientists created a lamb named Dolly from a single cell. Miraculously，the cell had been taken from the udder of adult sheep，which showed the first cloning experiment was successful.

When the cloning technology improves so quickly，many scientists and doctors have different opinions. Someone thinks it is good but someone thinks it is bad. Cloning can bring many benefits to the human，such as rejuvenation，helpful for defective genes，liver failure，kidney failure and leukemia. These diseases are very