ⅰ.用所给单词的适当形式填空 1．buses run ________(frequent)between the city and the airport. 2．this book requires a great deal of ________(concentrate)． 3．he has been with the company since its ________(create) in 1988. 4．no person shall enter the area without official ________(permit)． 5．the reading room is ________(design)to contain 200 students.
