题目内容
假设某程序语言的文法如下：S→SaT｜TT→TbR｜RT→PdR｜P P→fSg｜e其中：VT=a，b，d，e，f，g，VNS，T，R，P，S是开始符号。那么，此方法是 (38) 方法。这种文法的语法分析通常采用优先矩阵，优先矩阵给出了该文法中各个终结符之间的优先关系 (大于，小于，等于，无关系)。在上述文法中，某些终结符之间的优先关系如下：b (39) a：f (40) g；a (41) a；d (42) d。 （38）处填（）。
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就材料3和材料4，概括材料所反映的主要问题，并对该问题进行简单分析。要求：概括准确，分析透彻，条理清晰，字数不超过250字。
There are many kinds of friends. Some are always ( 1 ) you, but don’t understand you. Some say only a few words to you, but understand you. Many people will step in your life, but only ( 2 )friends leave footprints. I shall always recall the autumn and the girl with the ( 3 ). She will always bring back the friendship between us. I know she will always be my best friend. It was the golden season. I could see the yellow leaves ( 4 )with the cool ( 5 ). In such a season, I liked walking alone on the roads covered with leaves, ( 6 )to the sound of them. Autumn is a ( 7 )season and life is uninteresting. The free days always get me ( 8 ). But one day, the sound of a violin ( 9 )into my ears like a stream flowing in the mountains. I was so surprised that I jumped to see what it was. A young girl, standing in the wind, was ( 10 )in playing her violin. I had ( 11 )seen her before. The music was so nice that I listened quietly. Lost in the music, I didn’t know that I had been ( 12 )there for so long but my existence did not seem to disturb her. Leaves were still falling. Every day she played the violin at the corner of the building ( 13 )I went downstairs to watch her performance. I was the only listener. The autumn seemed no longer lonely and life became ( 14 ). ( 15 )we didn’t know each other, I thought we were already good friends. I believe she also loved me. Autumn was nearly over. One day, when I was listening carefully, the sound suddenly ( 16 ). To my astonishment, the girl came over to me. “You must like music from the violin.” she said. “Yes. And you play very well. Why did you stop” I asked. Suddenly, a ( 17 )expression appeared on her face and I could feel something unusual. “I came here to see my grandmother, but now I must leave. I once played very badly. It was your listening every day that ( 18 )me.” she said. “In fact, it was your playing ( 19 )gave me a meaningful autumn,” I answered, “Let’s be friends.” The girl smiled, and so did I. I never heard her play again in my life. I no longer went downstairs to listen to her. Only thick leaves were left behind. But I will always remember the fine figure (身影) of the girl. She is like a ( 20 )―so short, so bright, like a shooting star giving off so much light that makes the autumn beautiful.
The dog, called Prince, was an (26) animal and a slave to Williams. From morning till night, when Williams was at home, Prince never left his sight, practically (27) all other members of the family. The dog had a number of clearly (28) duties, for which Williams had (29) trained him and, like the good pupil he was, Prince lived for the chance to (30) his abilities. Williams was an engine driver. Over the years Prince got to know when his master would leave the house and return, and the dog did not waste this (31) . If Williams overslept, as he often did, Prince (32) at the bedroom door until he woke, much to the (33) of the family. On his return, Williams’ slippers were brought to him. A curious thing happened to Williams during the snow and ice of last winter. (34) . He was so badly shaken that he stayed in bed for three days; and not until he got up and dressed again did he discover that he had lost his wallet containing over fifty pounds. (35) . However, two days later--that was five days after the fall--Prince dropped the wallet into Williams’ hand. (36) and a few other papers.
根据第1题概括出的问题，谈谈如何将家电汽车以旧换新、下乡等政策落到实处。要求：有针对性、可行性，字数不超过400字左右。
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