【写法借鉴】作为一篇说明文，作者在文中运用了大量的确切的数据，如：“我国70%的沙质海岸和粉沙淤泥海岸遭受海水侵蚀，全国114个沿海城市不同程度地遭受海水侵蚀，海水入侵总面积达1000多平方公里，每年因此造成的经济损失达8亿多元……”这样，增强了可信性和说服力。

【片段仿写】请你对当地的环境做个调查，搜集第一手资料，了解有关状况，写一段说明性文字。(100字左右)

某校9年2班有2名男生和3名女生报名参加志愿者活动。若从报名者中随机选取2名学生参加志愿者活动，请你用列表法或画树状图求选取的两名学生是一男一女的概率

阅读理解
    American country music is also known as(被称为)country Western music．It has a very long history．It comes from the folk songs of immigrants(移民)from Britain．
    Country music uses simple music and words to express everyday feelings such as loneliness，love，and sadness．That is to say，country music describes life．It talks about friends and enemies，trucks and roads，farms and crops．People in many parts of the world like country music，because everyone can understand what the music is about．
    Country Western music became popular first among cowboys(牛仔)in the American West courttryside．Cowboys had to take care of cows day and night．When they were alone with the cows，they often sang beautiful and peaceful songs to calm the animals and to overcome their own fear．They were not well—educated and so they sang about their daily life in very simpie words．They played guitars，violins，and other instruments．  In the south of America，many people added instruments from their homes，like bottles and spoons．  When cowboys visited their friends and families on holidays like Thanksgiving，they usually sang and played country Western music．
    In recent years，many musicians have made country Western music a little different from the one in the past．These changes make the songs sound even better．Today singers such as Garth Brooks， Reba McEntire，Emmylou Harris，Lyle Lovett，Eddie Rabbitt，LeAnn Rimes，Randy Travis，and a group called Alabama are singing and playing in different styles．They have brought country Western music more and more fans from all over the world．

读西安市附近略图，西安市作为古都的区位因素是(　　)

①地形　②气候　③河流　④铁路

新华社巴西利亚2009年9月17日电 人类的开发是导致雨林被破坏的直接原因，巴西政府17日宣布，拟立法严禁增加甘蔗种植面积，以保护亚马孙雨林免遭进一步砍伐。结合图和所学知识，分析亚马孙地区热带雨林分布面积广阔的原因包括 (  )

①地势西高东低，有利于东南风的深入 ②受南赤道暖流的影响 ③受秘鲁寒流的影响 ④平原面积广阔