Lesson One

The Water Cycle

Water on Earth is always changing. Its repeating changes make a cycle. As water goes through its cycle, it can be a solid (ice), a liquid (water), or a gas (water vapor). Ice can change to become water or water vapor. Water can change to become ice or water vapor. Water vapor can change to become ice or water.

此主题相关图片如下：

How do these changes happen? Adding or subtracting heat makes the cycle work. If heat is added to ice, it melts. If heat is added to water, it evaporates. Evaporation turns liquid water into a gas called water vapor.

If heat is taken away from water vapor, it condenses. Condensation turns water vapor into a liquid. If heat is taken away from liquid water, it freezes to become ice.

The water cycle is called the hydrologic cycle. In the hydrologic cycle, water from oceans, lakes, swamps, rivers, plants, and even you, can turn into water vapor. Water vapor condenses into millions of tiny droplets that form clouds. Clouds lose their water as rain or snow, which is called precipitation. Precipitation is either absorbed into the ground or runs off into rivers. Water absorbed into the ground is taken up by plants. Plants lose water from their surfaces as vapor back into the atmosphere. Water that runs off into rivers flows into ponds, lakes, or oceans where it evaporates back into the atmosphere. The cycle continues.

There are six important processes that make up the water cycle. These are:

Evaporation

Evaporation is the process where a liquid, in this case water, changes from its liquid state to a gaseous state. Liquid water becomes water vapor. Although lower air pressure helps promote evaporation, temperature is the primary factor. For example, all of the water in a pot left on a table will eventually evaporate. It may take several weeks. But, if that same pot of water is put on a stove and brought to a boiling temperature, the water will evaporate more quickly.

During the water cycle some of the water in the oceans and freshwater bodies, such as lakes and rivers, is warmed by the sun and evaporates. During the process of evaporation, impurities in the water are left behind. As a result, the water that goes into the atmosphere is cleaner than it was on Earth.

Condensation

Condensation is the opposite of evaporation. Condensation occurs when a gas is changed into a liquid. Condensation occurs when the temperature of the vapor decreases.

When the water droplets formed from condensation are very small, they remain suspended in the atmosphere. These millions of droplets of suspended water form clouds in the sky or fog at ground level. Water condenses into droplets only when there are small dust particles present around which the droplet can form.

Precipitation

When the temperature and atmospheric pressure are right, the small droplets of water in clouds form larger droplets and precipitation occurs. The raindrops fall to Earth.

As a result of evaporation, condensation and precipitation, water travels from the surface of the Earth goes into the atmosphere, and returns to Earth again.

Surface Runoff

Much of the water that returns to Earth as precipitation runs off the surface of the land, and flows down hill into streams, rivers, ponds and lakes. Small streams flow into larger streams, then into rivers, and eventually the water flows into the ocean.

Surface runoff is an important part of the water cycle because, through surface runoff, much of the water returns again to the oceans, where a great deal of evaporation occurs.

Infiltration

Infiltration is an important process where rainwater soaks into the ground, through the soil and underlying rock layers. Some of this water ultimately returns to the surface at springs or in low spots downhill. Some of the water remains underground and is called groundwater.

As the water infiltrates through the soil and rock layers, many of the impurities in the water are filtered out. This filtering process helps clean the water.

Transpiration

One final process is important in the water cycle. As plants absorb water from the soil, the water moves from the roots through the stems to the leaves. Once the water reaches the leaves, some of it evaporates from the leaves, adding to the amount of water vapor in the air. This process of evaporation through plant leaves is called transpiration. In large forests, an enormous amount of water will transpire through leaves.

水的循环

地球上的水处于不断变化当中。不断重复的变化形成一个水的循环。处于循环变化中的水可能是固（如冰）、液体（如水）、气体（如水蒸汽）。 冰能转化成水或者水蒸汽。水蒸气能变成冰或者水。

此主题相关图片如下：

这些变化是如何发生的呢？增加或者降低热量能形成整个水圈。 如果给冰加热，它就会融化成水。如果给水加热， 就会蒸发。蒸发能让液态水变成气态即水蒸气。

如果将水蒸气的热量不断降低，它就会凝结。凝结能让水蒸汽变成液体。如果将液态水的热量降低，水就会开始凝固变成冰。

水圈被称为水循环。 在水的循环中，来自于海洋、湖泊、沼泽、河流、植物甚至我们人体的水变成了水蒸气。 水蒸气凝结成无数的微小颗粒从而形成了云。云中的水最后以雨水或雪花的形式降落下来，就被称为降雨（降雪）。降雨有可能被地面吸收，也可能流入河流。 被地面吸收的水分又被植物吸收。植物中水分又会从它的表面蒸发回到大气中去。这样这个循环就一直进行下去。

在水的循环中，有六个非常重要的组成环节。 各环节如下：

蒸发

在蒸发的过程中，液体，这里指水，将会从它的液体状态变成气体状态。液态水变成了水蒸气。尽管较低的空气压力能促进蒸发，温度是最根本的因素。 例如，桌面上水壶里的所有的水最终都将被蒸发。这一过程可能需要几个星期。但是，如果将同样一壶水放到炉子上，或加热到沸腾的温度，水的蒸发将会快很多。

在整个水循环过程中， 海洋或一些淡水体，如湖泊、河流中的部分水被阳光加热而蒸发。 在蒸发的过程中 ，水中的杂质被留了下来，这样蒸发到大气中的水将会被地球上的更清洁。

凝结

凝结与蒸发的过程刚好相反。当气体变成液体时就发生凝结。当水汽的温度不断下降时凝结就会产生。

凝结产生的水珠微粒非常的小，它们会漂浮在大气中。无数的水珠微粒漂浮在大气中就会形成天空中云朵或地面层的雾。 水凝结成小水珠的条件是大气中有微小的尘土， 水汽在尘土周围形成小水珠。

降雨

当温度和大气压处于一定状态下时，云中水珠微粒将形成更大的颗粒，就会产生降雨。雨点落向地面。

在蒸发、凝结和降雨的过程中，水从地球的表面蒸发到大气中，然后又回到地面。

地面径流

在降雨过程中，大部分落到地面的水会在泥土的表面汇成流，从小山流向小溪、小河、池塘或者湖泊。小溪不断变大，然后汇成河，最终流向海洋。

地面径流是水循环中很重要的一部分， 因为通过干的径流，大部分的水最后返回到海洋，在海洋的上空会形成更多的蒸发。

下渗

下渗是一个很重要的过程，在这过程中雨水将渗透土壤以及更深的岩石层，来浸润地面。 其中部分水最终以喷泉或在低地势的地方返回到地面。 有些继续保留在地层下，形成地下水。 随着水下渗穿过土壤和岩石层时，水中的许多杂质被过滤掉。这一浸润过程有利于清洁水。

散发

水循环过程中最后重要一环。当植物从土壤中吸取水分，水分从植物的根和茎部到达叶子。一旦水分到达叶子，就产生蒸发，植物叶子蒸发出的水汽增加了大气中水汽量。 通过植物叶子来蒸发的过程叫做散发。 在大面积的森林，大量的水汽通过植物的叶子散发到大气中。

1. vapor n. 水汽

2. subtract v. 减去

3. subtract sth (from sth) 从…. 减去…

4. evaporation n. 蒸发

5. condensation n. 凝结、凝聚

6. hydrologic cycle 水文循环

7. droplet

8. precipitation n. （雨、雪、雹子）降落

9. gaseous adj. 气体的、含气体的、

10. freshwater n. 淡水

11. impurity n. 杂质

12. infiltration n. 渗入、渗透

13. infiltration of sth into sth 渗入、混入

14. ultimately adv. 最终、基本上

15. transpiration n. （叶面的水汽）散发、蒸发

16. stem n. 茎、干

SUPPLEMENTARY READING

Baggage Declaration Form

Just as passenger processing is the most common activity for new Customs officers, the Declaration Form is the Form new Customs officers will most frequently encounter. Passengers at some border passes are not usually required to complete a Baggage Declaration Form. With few exceptions most passengers on commercial vessels or aircraft must complete Declaration Form prior to Customs processing. The Customs provides passengers with a blank Declaration Form, which contains NOTES and other Customs information. This blank Form is available free from Customs and through agents.

If the Baggage Declaration Form is properly completed by the passengers and utilized by the Customs officer, each passenger can be processed efficiently and expeditiously. The Form provides the Customs officer with basic information about the passenger. It provides the passenger with information about Customs regulations and those of other agencies.

If one takes a careful look at the Baggage Declaration Form, it becomes apparent what information is provided and how it is useful．

There are seven co1umns in the top left-hand corner of the Form．

Co1umns l—3 contain the passenger’s name，nationality and passport number．The information can be verified by reviewing the passenger’s passport or other travel documents．

Column 4 tells the Customs officer from／to which country the passenger is traveling. This information can be verified by reviewing the airline ticket．

Column 5 indicates the number of the accompanying family members. This gives the Customs officer a complete picture of the family group facing him and help him determine if they are able to grant exemptions．

Columns 6 & 7 indicate how many pieces of hand baggage and checked baggage the passenger is carrying.

The Black Column 1 on the left asks the passenger if he is carrying over RMB1,OOO or any Chinese currencies．

The B1ack Column 2 asks the passenger if he is carrying over 50 gram gold & silver ornaments．

The B1ack Columns 3—5 ask questions which are about trip necessities：camera ，tape recorder，video & movie camera (brand & piece)．

The Red Columns on the left are about the other articles due to Customs procedures．These Columns ask the passenger if he is carrying goods or samples，recorded video tape，printed matters，antiques (Yes or No)．

There are some Red Co1umns in the top right-hand corner of the Form. The Red Columns on the right require a declaration of durable consumer goods (price >=RMB 50) and gifts (total price>=RMB 50). This information is essential in applying exemptions and calculating duty．

The fo11owed Columns in the lower“right-hand of the Form are about the unaccompanied baggage：how many pieces are they? Which Customs are they to be imported through within 3 months?

Beneath the Columns of the unaccompanied baggage，there are two blanks：one is for the signature to be signed by the passenger，the other is for the date of signature．The signature and the date will certify that they are making a truthful declaration. This can be an important piece of evidence in the case of a passenger who claims ignorance of the law．

The 1ast two items in the bottom right-hand corner of the Form are：Customs remarks & Customs endorsement. They must be completed by the Customs officer on duty according to the clearance of the Passenger.

On the reverse of the Declaration Form are three paragraphs which summarize a passenger’s responsibilities in declaring items to Customs. This information should be brought to the attention of and explained to any passenger who appears confused or uncertain of what is necessary to declare to Customs．

Additional Information

The Importation of the Fo1llowing Articles is prohibited

1. Arms, ammunitions and explosives of all kinds;

2. Radio transmitter-receivers and principal parts;

3. Renminbi (with the exception of those in compliance with an agreement or protocol on the exchange of national currency notes);

4.Manuscripts, printed matters, films, photographs, gramophone records, cinematographic films, loaded recording tapes and video-tapes, etc., detrimental to China’s political, economic, cultural and moral interest;

5. Poisonous drugs, herb-forming drugs, opium, morphine, heroin, cocaine, marihuana, hashish, ICE, head-shaking balls, Ellisa;

6. Animal, plants, and products here of infected with diseases, germs and insect pests;

7. Unsanitary foodstuffs and germ-carrying foodstuffs from infected area;

8. Other articles, the importation of which is prohibited by state regulation.

The exportation of the Following Articles is Prohibited

1. Arms, ammunitions and explosives of all kinds;

2. Radio transmitter-receivers and principal parts;

3. Renminbi and securities, etc., in Renminbi;

4. Foreign currencies, bills and securities in foreign currencies (with the exception of those allowed to be taken out);

5.Manuscripts, printed matters, films, photographs, gramophone records, cinematographic films, loaded recording tapes and video-tapes, etc., which contain state secrets, or otherwise prohibited.

6. Valuable cultural relics and rare books relating to Chinese revolution, history, culture and art;

7. Rare animals, rare plants and their seeds;

8. Precious metals and articles made thereof, jewelry, diamonds and ornaments made thereof (with the exception of those within the quantity allowed to be taken out by outgoing passengers);

9. Other articles the exportation of which is prohibited by state regulations.

Customs of the People’s Republic of China

Declaration for Passengers

NOTE

1. This “Declaration” may be used by both incoming and outgoing passengers.

2. Animal, plants and their seeds, and articles prohibited in importation or exportation must be declared and presented to the Customs to be dealt with according to the relevant regulations.

3. Articles (including gifts and samples) other than those specified in the description column should be declared in the blank lines below.

4. Articles declared in this form, if marked with "△" by the Customs, must be brought out by the passenger while leaving this country.

5. This declaration, after being duly stamped by the Customs, is to be kept by the passenger until his return trip and then it should be presented to the Customs for verification. In case this declaration is lost or altered by the passenger, it will be dealt with as a case of breach of the Customs regulations.

6. All specified items must be truly declared. False declaration and concealment of these articles will be dealt with by the Customs according to the law.

行李物品申报单

正如对旅客进行查验、放行是一名新海关关员日常最普通的工作一样，申报单也将是新海关关员遇到的最频繁的单证。在一些陆地边境进出境的旅客并不经常要求其填写行李物品申报单。但以乘船或坐飞机的方式进出境的旅客，除少数例外外，大多数都必须在进行海关通关前填写申报单。海关会向旅客提供一份印有注意事项及其它海关规定的空白申报单。这种空白申报单也可免费通过代理人从海关获得。

如果旅客据实填写了行李物品申报单，并被海关关员接受，那么每位旅客便可迅速有效地办理结关手续。申报单向海关关员提供了旅客的基本信息，同时也使旅客了解了海关及其它机构的有关规定。

如果仔细的看一下行李物品申报单，便可清楚的了解它提供了哪些信息，以及这些信息是怎样起作用的。

在申报单的左上角，有7栏：

第1—3栏为旅客姓名、国籍及护照编号栏。这些信息可以通过查阅旅客的护照和其它旅行证件来加以核实。

第4栏告诉海关关员旅客来自哪个国家，或将要去哪国旅游。这些信息可以通过查阅机×××屏蔽字符×××来加以核实。

第5栏指出随行家庭成员的人数。这栏信息可使海关关员对眼前的家庭有一整体认识，并有助于他决定是否免验其他成员。

第6、第7栏写的是旅客随身携带的行李以及已查验的行李件数。

左边第一黑栏询问旅客是否携带超过1,000元的人民币或是否携带中国货币。

第二黑栏询问的是旅客是否携带超过50克的金银饰品。

第三—五黑栏是有关旅行必需品的问题：照相机、录音机、摄像机和摄影机(品牌和件数)。

左边的红栏是有关其它须经海关查验的货品。这些栏询问旅客是否携带有货物或样品、录像带、印刷品、文物（是或否）。

申报单右上角也有一些红栏。右边的红栏要求对应税消费品（价值大于等于50元人民币）和礼品（总价大于等于50元人民币）的申报。这些信息对是否适用免税及计算关税税额至关重要。

申报单右下角各栏是有关非随身携带行李的问题：共有几件？三个月内从哪个海关入境？

在非随身携带行李物品栏的下面，有两个空栏：一个用于旅客签名，另一个是签名日期栏。旅客签名及写上签名日期以证明他们的申报是真实的。如果旅客日后称其不了解有关法律，这个可作为重要证据。

申报单右下角有最后两项内容，即海关批注和签字。两项内容由值班关员按旅客结关情况填写。

在申报单的背面，有三段文字，简要介绍了旅客在向海关申报物品时应负的责任。对于不清楚或不知道哪些物品应向海关进行申报的旅客，海关关员应将此信息提请他们注意并加以解释。

附加信息

下列物品禁止进境

1. 各种武器、弹药和爆炸物品；

2. 无线电收发报机及主要零件；

3. 人民币（按照国家间货币互换协定或议定书办理的除外）；

4. 对中国政治、经济、文化、道德有害的手稿、印刷品、胶卷、照片、唱片、影片、录音带、录像带等；

5. 毒性毒品、毒品、鸦片、吗啡、海洛因、可卡因、大麻、印度大麻、冰毒、摇头丸伊利萨等；

6. 带有疾病、病菌、害虫的动物、植物及其产品；

7. 不卫生食品和来自疫区携带病菌的食品；

8. 国家法规规定禁止进境的其它物品。

下列物品禁止出境

1. 各种武器、弹药和爆炸物品；

2. 无线电收发报机及主要零件；

3. 人民币及其×××屏蔽字符×××据和有价证券；

4. 外币及其有价证券（允许带出的除外）；

5. 内容涉及国家机密的手稿、印刷品、胶卷、照片、唱片、影片、录音带、录像带等物品及其它禁止出境的物品；

6. 珍贵文物和有关中国革命、历史、文化和艺术的珍稀书籍；

7. 珍奇动物、植物及其种子；

8. 贵金属及其制品，珠宝，钻石及由钻石制成的饰品（允许由出境旅客带出境的数量范围内的除外）；

9. 国家法规规定禁止出境的其它物品。

中华人民共和国海关旅客申报单

注意事项

1. 此申报单可适用于进境和出境旅客；

2. 禁止进出境的动物、植物及其种子必须申报，并交由海关按相关规定进行处理；

3. 说明栏中列明的物品以外的物品（包括礼品和样品），应在下面横线上申报；

4. 本申报单上申报的物品，如果海关在其上加注“△”标志，则旅客在离开本国时必须携带出境；

5. 本申报单经海关盖章后，交由旅客保存，直至其返回。在其返回本国时，旅客应将原申报单交由海关核查。如果旅客丢失或更改此申报单，将视为违反海关法的行为进行处理；

6. 所列项目必须如实申报。对于伪报和藏匿物品行为，将由海关根据有关法律进行处理。

怎么是不是没一个人看得懂啊，没人顶。

顶!顶!顶!顶!顶!顶!顶!顶!老赖,真不简单啊,厉害厉害,以后可要多发这样的帖子哦,太是受教了!虽然我大多数看不懂,谁叫我是一个爱国的水利中国人呢!

我也来顶一个！！！

图文解说的不错哦。找本字典来读。