第一节:单项填空(共l5小题;每小题l分,满分l5分) 
    从A、B、C、D四个选项中,选出可以填人空白处的最佳选项,并在答题卡上将该项涂 黑。 
21.Some of the exercises appear to be ______ ones that you have done, but after taking ______second look, you will find that they are different.
       A./, the                 B.the, the              C.the, a                 D./, a
22.I'm amazed to hear from my old friend again.______,it is ten years since we met last.
       A.In a word          B.What' s more       C.That' s to say       D.Believe it or not