--Is it _____ pen? --Yes. It' s ______ orange pen. A a; a B. an; an C. a; an D. an; a
—Have you heard of the songs sung by the first lady---Peng Liyuan? —Of course! ___________ beautiful voice she has! —I agree.
—I knocked into a tree when I went to the bus stop for my friend. —I suppose you _____too fast.
If all the plants on the earth die, _______ people _________animals will be able to live.
—__________ do you go to Dalian on business? —Never. A. How long B. How often C What time D. When
—Is there __________ in today’s newspaper? —Yes, the top news is about H7N9.