Ⅰ.单句语法填空
1．The result of the research is that the risk of the program to be carried out is__________(reduce)．
答案： reduced
2．His magic is __________(confuse)，and I can never figure out how he made the plane disappear.
答案： confusing
3．The story tells us that the__________(discover) of fire was one of the biggest inventions of man.
答案： discovery
4．We welcome__________(comment) and suggestions from readers，and we look forward to hearing what you think of this new product.
答案： comments
5．The young man often does some exercise to build ________ his body.
答案： up
6．Organic farming will keep the soil rich and free__________ disease.
答案： of
