阿糖胞苷抑制核酸合成的机制是（） A.抑制胸苷酸合成酶 B.阻止嘌呤核苷酸形成 C.

     Five and a half years ago my father was suddenly rushed to the hospital for an operation.At the time,we had no idea that he was__1__ill.The operation did not go well and he remained__2__.Due to the laws of
our state,we were__3__to keep him on a ventilator (呼吸机) for 72 hours against his wish of stopping
medical treatment if he was too ill.
     At the end of day two,I was__4__in the waiting room and watching others walk their fathers around
who had had__5__.Typically,I am very happy for others that are__6__,but that evening,I guess I was a
little__7__because I finally realized I would__8__be able to hold my father's hand and walk down the hall again.
     I had to jump up and run down the hall to__9__everyone.This was not in my nature but I just had to be__10__.After running for what seemed like a long time,I went into a rest room.I sat in a stall (小隔间) and__11__for at least five minutes.
     When I came out of the stall there was a__12__by the sink.I went to__13__on the water to wash my
face and she came to hug me though I didn't know her.She held onto me__14__I finally stopped crying.
Then she grabbed a paper towel,wet it and__15__it to me.She looked at me and smiled and then left.She never spoke one word but she touched my__16__.
     She__17__me that you do not need to be a conversationalist to help__18__the hurt in others.Never
__19__to hug someone who may need it today.You can make a__20__in someone's life without ever
speaking one word.