材料一：汉武帝时，只叫地方长官每年要选举些孝子廉吏，但后来孝廉充斥仕途，别的进仕之路都为之阻塞了，于是大家都争要为孝廉。本来所谓孝廉，一种是孝子，另一种是廉吏。后来规定每郡满二十万户口的只能举一个，如是则孝廉不分，仅成一个参政入仕的资格而已。后来又请托舞弊，逼得朝廷于察举孝廉后再加上一番考试。如是则全失却原来察举孝廉之用意。从此以后，无论选举或考试，都是分区定额的。经济文化落后的地区和经济文化进步的地区，都一样照人口比例来考选。

——摘编自钱穆《中国历代政治得失》

材料二：中国地方行政区划，自秦汉以来，基本上按山川地形的自然境界建置。……元统治者吸取了汉唐以来地方割据势力据险对抗中央政府这一教训，打破了自然的疆界，极力避免某一地区成为地方长官据险称雄的国中之国。地方区域的设置，人为地使自然区域割开，造成犬牙交错的局面

——李怀孔《中国古代行政制度史》

材料三：元朝同宋一样，把地方分成路、府、州、县，而实际上元代的地方政权不交在地方，乃由中央派行中书省管理。行省长官是中央官而亲自降临到地方。……所以行中书省正名定义，并不是地方政府，而只是流动的中央政府

——钱穆《中国历代政治得失》

    A MENTORING (导师制) program is giving life changing opportunities to Banbury youth.

    Young Inspirations was founded two years ago to provide mentoring sessions for students and unemployed young adults aged 11 to 21.

    Alex Goldberg, the program's founder, said; "We set up Young Inspirations because we wanted to give young people experiences which will potentially be life changing and broaden their outlook.

    "We try to create work experience opportunities that will really make a difference to our youth. For example, we've secured internships (实习) with world-famous firms such as Honda.

    "At a time of funding cutbacks where schools are finding it more and more difficult to offer this kind of mentoring, it is extremely important that these opportunities are available both to help youth with their school work and grades and to give them opportunities which may help shape their futures. " Kieran Hepburn, 14, is one of a group of Banbury youth who has benefited from the program so far. In October the Banbury School pupil was accompanied by Young Inspirations staff to Paris where he was an observer at the United Nations Educational, Scientific and Cultural Organization's (UNESCO) International Youth Forum (论坛).

    The event was held for young people from around the world, to seek their views on how the future of youth and education should look. Kieran joined several hundred observers mostly in their 20s and was the only UK school pupil to attend the event. Kieran thinks the trip was a life changing experience. " Before we left I didn't quite know what to make of it but when we got there we didn't stop, it was amazing," he said, " We went to three or four hours of debates each day and then did something cultural each afternoon. "

    The main theme of the forum was how youth can drive change in political and public life. It dealt with issues (问题) such as drug abuse, violence and unemployment.

    Kieran said: " It has really helped me to improve my confidence and social skills as well as my school grades and I was voted most improved pupil at school in August. "

    The Young Inspirations mentoring sessions take place each Friday in Banbury. For details visit www.younginspirations.com.

图中示意我国四川西部某山地东坡土壤中磷累积量的垂直变化，与磷高累积区相比，该山坡2000~3000米处（    ）

欧洲航海者的日记显示，在15世纪以前，毛里求斯岛上的渡渡鸟随处可见。后来欧洲殖民者到达了毛里求斯岛，他们疯狂地捕猎肉味细嫩鲜美的渡渡鸟，加之殖民者带来的猪、狗、鼠等，渡渡鸟灭绝了。渡渡鸟灭绝之后，毛里求斯岛上的卡尔瓦利亚树也面临灭绝的危险。这种树的果皮坚厚，种子很难萌发。渡渡鸟最喜欢吃卡尔瓦利亚树的果实，果实经过渡渡鸟的消化道后，果皮变薄了，果实中的种子得以正常萌发。

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