从A、B、C、D四个选项中，选出可以填入空白处的最佳选项，并在答题卡上将该项涂黑.
6.Each member of ______ Green Peace Club is required to gain _____ better understanding of their system.
A. the; the B. the; a C. /; a D. /; /
7.Alice cares most about her clothing, who is followed by Mary, while Della shows _____ interest in fashion.
A. more B. the most C. less D. the least
8.—How about my food? I ________ here for almost half an hour.
—I’m sorry, sir. It must be ready by now.
A. have been sitting B. am sitting
C. had been sitting D. was sitting
9.The large grassland, reaching out far away, looks extremely beautiful ________ the blue and clean sky.
A. with B. against C. through D. beyond
