单项选择题
It was()great shock to the world that two airplanes crashed into() World Trade Center in New York on September 11, 2001.
A．a; / B．the; the C．a; the D．/; the
单项选择题 Radio Star,()by the English Department, is very popular with the students.
单项选择题 He said that books on()popular science are in()short supply.
单项选择题 As it turned out to be a problem of no importance, we()so much time look- ing into it.
