题目内容
Cloning is a way of 1. (make) an exact copy of another animal or plant. Cloning has two major uses. Firstly,gardeners use 2. to produce plants. Secondly,it is 3. (value) for medical research on animals. Cloning plants is straightforward but the cloning of animals is 4. (complicated) .The procedure is difficult 5. (undertake) . In 1996,scientists succeeded 6. cloning Dolly the sheep. Then came the disturbing news
7. Dolly was ill. Altogether Dolly 8. (live) for six and a half years. Dolly's appearance raised 9. storm of objections. Governments became nervous and many forbade research into human cloning. Scientists still wonder 10. cloning will help or harm us and where it is leading us.
1. making 2. it 3. valuable 4. more complicated 5. to undertake 6. in 7. that 8. lived 9. a 10. whether