题目内容
仔细阅读,尽可能使用本单元学过的词汇补全下面的短文
Mr Smith,a 1. (退休的) professor,who had been 2. (从事) cloning,gave us a report yesterday. He 3. (给.. 印象) us as a learned person and his talk was 4. (中断) by our warm applause 5. (不时) .
Mr Smith explained that cloning was a way of making an 6. (精确的) copy of another animal or plant. After many years' efforts,scientists' determination and patience 7. (是值得的) and they made a great 8. (突破) in 1996. A sheep was cloned successfully. However,she lived six and a half years 9. (总共) .Scientists were 10. (沮丧) .How to avoid such problems 11. (闲扰) scientists. Mr Smith also said the copy had many 12. (缺点) .For example* they couldn't 13. (抵抗) diseases from their families.
When asked whether we could clone extinct animals ? Mr Smith said human beings were 14. (未能) to do this. These efforts were 15. (白费力气) .
1.retired 2. undertaking 3. struck 4. interrupted 5. from time to time 6. exact 7. paid off 8. breakthrough 9. altogether/in all 10. cast down 11. bothered 12. drawbacks 13. resist 14. unable 15. in vain