消费税的特点包括( )。A．征收范围具有选择性 B．征税环节具有多样性 C．征收方

Scientists find that hardworking people live longer than average men and women．Career （职业）women are healthier than housewives．Evidence shows that the jobless are in poorer health than the jobholders．An investigation shows that whenever the unemployment rate increases by 1％，the death rate increases by 2％．All this comes down to one point．work is helpful to health．

Why is work good for health? It is because work keeps people busy away from loneliness．Researches show that people feel unhappy, worried and lonely when they have nothing to do．Instead the happiest are those who are busy．Many high achievers who love their careers feel that they are happiest when they are working hard．Work serves as a bridge between man and reality. By work people come into contact with each other．By collective（集体的）activity they find friendship and warmth．This is helpful to health．The loss of work means the loss of everything．It affects man spiritually and makes him ill．

Besides，work gives one a sense of achievement．Work makes one feel his value in society．When a writer finishes his writing or a doctor successfully operates on a patient or a teacher sees his students grow, they are happy beyond words．

From the above we can come to the conclusion that the more you work the happier and healthier you will be．Let us work hard and study hard and live a happy and healthy life．

1．What may be the reason why housewives are not as healthy as career women?

A．Housewives are poorer than career women．

B．Housewives have more children than career women．

C．Housewives have less chance to communicate with others．

D．Housewives eat less food than career women．

2．Which of the following statements is TRUE according to Paragraph 2 ?

A．Busy people have nothing to do at home．

B．High achievers don’t care about their families．

C．There is no friendship and warmth at home．

D．A satisfying job helps to keep you healthy．

3．The best title for this passage may be “               ”

A．People Should Find a Job

B．Working Hard Is Good for Happiness and Health

C．People Should Make More Friends by Work

D．The Loss of Work Means the Loss of Life

阅读下面短文，回答下 * * 道题
人类总是依据自身的利益评价外部事物，将之分成优劣好坏，而大自然则另有一套行为规范与准则。现在人们闻之色变的沙尘暴，即由于强烈的风将大量沙尘卷起，造成空气混浊能见度小于千米的风沙天气现象，其实古已有之。它本是雕塑大地外貌的自然力之一，是大自然的一项工程，并且在全球生态平衡中占有一席之地。
在地质史上，风力对草原带的风化物质进行筛选分类：凡搬不动的粗大砾石，留在原地形成砾石戈壁滩：颗粒适中的粗砂和细砂被吹移到附近就地聚集成沙漠；颗粒微小的粉沙细土和微尘，则被强上升气流扬上天空，作中长距离的输送。我国黄土高原的黄土层就是沙尘经数百万年堆积而成的，华夏文明就是在这块沙尘累积的黄土地上诞生和发展起来的。澳大利亚的沙尘乘着南半球的西风掠过塔斯曼海，使新西兰火山岛上的土壤更为肥沃，因而被称作“澳大利亚出口的珍贵产品”。从非洲内陆吹向地中海的强风帮助古罗马人使用帆船从埃及运回小麦，但也将撒哈拉大沙漠的沙尘带到意大利、西班牙和法国。沙尘暴固然使空气中的可吸入颗粒物增加，然而由于沙尘含有碱性，又可中和大气中的酸性物质，减缓酸雨的发生。
风是地球上空的传送带，它将大陆的沙尘吹向海洋，又将海洋的水汽吹向大陆。沙尘和水汽相遇，便能结合为云，最终化作降水。可见，沙尘不仅在土壤的分布和补充上扮演着重要角色，而且在全球的水循环上也扮演着重要角色。可以说，沙尘也是决定全球生态平衡的因子。
然而，近百年来，沙尘暴却已成为影响人类生产生活的一大灾害。构成我国沙尘暴的物质材料，多来自干旱、半干旱的草原区。在人为活动的干预下，特别是由于森林大量砍伐，土地过度开垦，工厂盲目建设，排放不加控制，结果造成生态巨变：原来有沙漠的地方沙漠扩大了；没有沙漠的地方沙漠产生了；内陆河流程缩短，水量减少，沼泽地消失；河流两岸的绿色走廊枯萎死亡。这样，来自大西北的沙尘暴，一路上还源源获得裸地上新的沙尘源的补充，而且混入了工矿企业排放的有害成分和来自草原上牲畜粪便中的病菌病毒。总之，在受到人为因素的干扰后，自然界的风蚀速度已远远大于土壤的生成速度，一连串的灾害也就由此产生。歌德说过：“大自然是不会犯错误的，错误永远是人犯下的。”这或许能给我们某种启示。

下列对沙尘暴灾害加剧的原因，表述不正确的一项是______。

A．强上升气流把颗粒微小的粉沙细土和微尘扬上天空，作中长距离的输送

B．森林大量砍伐，土地过度开垦，工厂盲目建设，排放不加控制，造成生态巨变

C．沙尘暴中混入了工矿企业排放的有害成分和来自牲畜粪便中的病菌病毒

D．在受到人为因素的干扰后，自然界的风蚀速度已远远大于土壤的生成速度

水的特性为

A．润下
B．曲直
C．稼穑
D．从革
E．炎上

棉花的叶属完全叶。

病例对照研究又可称为（）

A.横断面调查

B.前瞻性研究

C.临床试验

D.回顾性研究

E.社区试验