语法填空（共10小题； 每小题1.5分，满分15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。
Animal testing
“It is always my ambition to be a research analyst studying amphibian anatomy（两栖动物解剖学 ）for the benefit of mankind.” said Dr. Cull to the high school students touring the laboratory. “My ancestors were all scientists and my father taught   1  that it is simply amazing to appreciate the details in each creature. I also hope that my research can help us to understand   2  humans influences these creatures so that we can know how to improve   3 (environment) problems and correct our wrongs.”
“You are very ambitious, Dr. Cull.” a bright, amber-haired girl said. “So you are looking for similarities between animals and humans?”
“Yes, and there are already enough findings. We know much about how anesthetics(麻醉药) work, for example,   4 (base) on clinical trials with rats.” “But I disagree with using animals for tests!” another student suddenly said. “  5  is often discussed whether using animals for testing is moral. But the knowledge we have collected about health, vaccines, antibiotics   6 (be) incredible. We have benefited a lot  7   animal research.”replied the Doctor.
“  8  I've seen videos of animals for research put in bad conditions.”Another student broke in.  “Oh, it seems that we've hit on   9  interesting topic.What about stepping into this conference room and discussing it   10 (far)？”