6. Xiamen is _____ most beautiful coastal city and I believe I will come for _____ second visit.

A. the; a          B. a; a     

C. the; the        D. a; the

7. —Can I help you?

—I’d like to buy a gift for my mother, _____at a proper price but of great use.

A. that             B. one          

C. anyone        D. everything