阅读下面短文,在空格处填入一个适当的词或者使用括号中词语的正确形式填空。
Jane: Hi, Jack. What are you doing there?
Jack: I'm reading a book about the American scientist,
George Washington Carver, who made great (contribute) to American farming.
Jane: I have read an article about him too. He was
born into a state of slavery.
Jack: Exactly right. But he became (know)
for the development of new crops for southern farmers main cash crop (经济作物) was cotton.
Jane: And I remember that he carried out many
(science) researches on the planting of crops, (aim) to improve
the farmers' quality of life.
Jack: You are right. However, he had an unfortunate
family. His parents had eleven children but all of his ten brothers and sisters
died young. addition, Carver and his mother was kidnapped (绑架)
and sold to Kentucky when he was just one week old. Though he (find) by
his master later, he never saw his mother again.
Jane: I can see he had a really hard childhood.
Jack: Yes. But his life changed after slavery was
abolished (废除). He was able to attend a school (build) for blacks. Then he
managed to get into the Tuskegee Institute, and began his crop research
(short) after graduation.
答案:【1】contributions【2】known【3】whose【4】scientific【5】aiming【6】In【7】was found【8】that【9】built【10】shortly