北京的“四合院”、上海的“石库门”、广东的“围村”、陕西的“窑洞”、福建 的“土楼，等民居建筑都与当地的自然环境息息相关，具有鲜明的地域文化特色，是中华民族共有的文化财富。各具特色的地域文化（    ）

①决定于各地千差万别的自然条件    ②蕴涵着中华文化的共性

③深受地理环境的影响和制约        ④长期相互借鉴而日趋同一

如图，M、N为山两侧的两个村庄，为了两村交通方便，根据国家的惠民政策，政府决定打一直线涵洞．工程人员为了计算工程量，必须计算M、N两点之间的直线距离，选择测量点A、B、C，点B、C分别在AM、AN上，现测得AM=1千米、AN=1.8千米，AB=54米、BC=45米、AC=30米，求M、N两点之间的直线距离．

    Hi, friends!My name is Jason．I am 11 years old and I live in Chicago in the USA．There are many holidays every year,and，my favorite one is Thanksgiving(感恩节)．It is a family holiday．

    Thanksgiving comes on the fourth Thursday of November every year．There is no school on Thanksgiving Day．That's great!My family gets together on Thanksgiving Day．My brother will drive home from New York．We always have a big dinner．My mom makes a lot of delicious food．My sister always helps her in the kitchen．We have roast turkey,sweet potatoes,pumpkinpie(烤火鸡，红薯，南瓜派)and so on．Turkey is a must in my family．Before dinner we give thanks to everything

wehave．

    I love this holiday very much．It teaches me to be thankful in life．My favorite thing about the holiday is being with my family and having a great time with them．That is a very important thing of the holiday．

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