从A、B、C、D四个选项中，选出可以填入空白处的最佳选项。
6．In memory of China’s Youth’s Day, celebration evening took place on our campus. It was success
A．a; / B．the; the C．a; a D．the; a
7． are cheap enough to be accessible to the students in schools.
A．All of reference these books B．All these of reference books
C．These all reference books D．All these reference books
8．---Will $200 the cost of the damage?
--- I’m afraid not. I need at least $100 more.
A．do B．include C．cover D．afford
9. --- John, you are caught late again.
--- Oh, _____________.
A. not at all B. just my luck C. never mind D. that’s my luck .
