四．语法填空。(共10小题，每小题1分，满分10分)
阅读下面短文，按照句子结构的语法性和上下文连贯的要求，在空格处填入一个适当 的词或使用括号中词语的正确形式填空。
On the other hand, Dolly’s 46 (appear) raised a storm of objections and had a great impact 47 the media and public imagination. It became controversial.
48 at present human egg cells and embryos 49 (need) for cloning research are difficult to obtain, newspapers wrote of evil leaders 50 (hope) to clone themselves to attain their ambitions. Religious leaders also raised moral questions. Governments became nervous and more 51 (conserve). Some began to reform their legal systems 52 forbade research into human cloning, but other countries 53 China and the UK continued to accumulate evidence of the abundant medical aid 54 cloning could provide. However, scientists still wonder whether cloning will help or harm us and 55 it is leading us.
