embryo. The 2. ________ was different because the team did not simply break off a cell from the embryo of the frog; they removed the nucleus and replaced it with the nucleus of an unfertilized frog egg cell.

This was a huge 3. ________ for modern day science as it was the first time that a nuclear transplant had ever been successfully conducted. Nuclear transplants still occur today, however the method 4. ________ slightly. In 1986 scientists from both the US and Britain claimed to have cloned the first mammal, big advances were made from those experiments. On July 5th 1996 Dolly was born. It took scientists over two hundred attempts to clone her but eventually it all 5. ________. Although 6. ________ Dolly lived six and a half years, not so long as hoped, it is still regarded as one of the greatest achievements of modern science.

Part 2 Learning about Language

I. 用适当的连接词填空。

1. The thought occurred to me ________ he might not be telling the truth.

2. -Do you have any idea ________ they are coming?

　-Probably Friday.

3. Along with the letter was Susan's promise ________ she would visit me this coming Christmas.

4. There's a feeling in me ________ we'll never know what a UFO is.

5. There remains a doubt among the public ________ the medicine is safe enough for children.

II. 根据括号内的提示翻译下面句子。

1. 我欠他10美元。(owe)

__________________________________________

2. 我睡觉的时候不要打扰我。(bother)

__________________________________________

3. 迈克明年从部队退役。(retire)

__________________________________________

4. 如果他们继续冒险, 一定会失败。 (be bound to)

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