--Is it _____ pen? --Yes. It' s ______ orange pen. A a; a B. an; an C. a; an D. an; a
— I’ll fly to Qingdao for my holiday this weekend. —Wonderful! _________.
— I hear your pen friend is visiting Suzhou at present. Is it the ______ time for her? — Yes, and she will come for a fourth time next summer.
They spend too much time ________ their homework.
Why the modern city with us? I’m sure we can have a good time there.
Please keep quiet, everybody! I have important to tell you.