_____ of the students who took part in the military training is 450.
| A．A number | B．A lot | C．Lots | D．The number |
17. ________ is expected, according to the on-line survey, is that prices of houses will not go up any longer.
| A．It | B．As | C．Which | D．What |
16. The story that follows _____ two famous characters of the Rocky Mountain gold rush days.
| A．concerns | B．states | C．relates | D．Refers |
15. An awful crash between an express train and a bus _____ , however, occur the other day in Russia.
A. does B. did D. has to D. had to
14. Many businessmen attended the Boao Forum (博鳌论坛) because they knew what _____ from the forum.
| A．to get | B．to be got | C．got | D．Getting |
13.The reason is____________ smoking tobacco causes illness.
A. why B because C. thatD. because of