地下水
地下水是指渗入到地下并将所有岩石空隙填满的水。到现在为止，雨水是最丰富的地下水资源，是地下水在水循环中的一个环节。普通的雨水会从地表、降水以及湖泊河流侵入到地下。在冒出地表之前，这些地下水有时会长时间留在地下。在我们脚下坚实的土地中竟然有足够的空间储存这些水，这在一开始会让人觉得难以置信。
地下水所需的储存空间多种多样。松散的砂子和砾石间有许多颗粒和小石子，他们之间的空隙是最常见的储存地下水的空间。由这些颗粒组成的水床非常普遍，通常位于看不见的土壤下方，在湍急的河流曾经流过的地方都能找到它们的踪迹。比如，冰河时代覆盖北美的巨大冰层逐渐融化，大量水从那儿流出。水里总会携带些石子、砾石和沙石，这就是所谓的冰河期的冰水沉积，这些颗粒会随着水流的减速而沉淀。
现代也有冰水沉积，尽管规模相对较小。凡是有携带泥沙的河流或者溪流从山谷流至相对平坦的地面时，砂石就随着水流速度的减慢逐渐沉淀;水流通常呈扇形扩散，它们所携带的砂石也会沉淀为光滑的扇形斜面。当河流汇入湖泊和海洋的时候也会有沉淀，这些沉淀最初在湖底或海底，但将来海平面下降或者陆地崛起时，它们就会分布于内陆，通常厚达几千米。
低地区域上的任何位置可能就是曾经的河床，后续被土壤覆盖而变成现在的样子。如果那些河床和沙洲现在位于地下水位之下，一定会有大量的地下水浸在它们的沙砾和沙石之间。
以上说的都是松散的沉积物，那些坚固的沉积物，也拥有以数万计的毛细孔来容纳水。因为最初颗粒间的缝隙通常并未完全被粘固的化学物质塞满，而且部分颗粒很可能在固化时或固化后被渗入的地下水溶解;结果这些砂岩最终变得和形成它的散沙一样多孔。
因此，不管沉积物是疏松还是坚固，他们中一定有空间。大部分结晶体岩石都非常坚硬，但也有例外，最常见的就是玄武岩，它是一种固化的火山熔岩，经常充满了微小气泡，从而变得十分多孔。
岩石的多孔性就是指其中空隙的比例。但需要注意的是，多孔性与渗透性是不同的。渗透性衡量的是水渗透物质的难易程度，它取决于与单个空隙以及连接空隙间裂缝的大小。
当充满水分的沉淀物或者岩石样本被放置在适合的干燥环境中时，大部分的水分会流干，但仍有部分水会继续附着在坚实的表面上。要不是因为表面张力，这些水分也会立刻蒸发，仅留下完全干燥的样本。因此，试验样本的含水量既包括可以流干的水，也包括不能流干的水。
这两种水的相对含量因岩石或沉积物种类不同而改变，即便它们有相同比例的空隙，还取决于空隙的大小。如果空隙很大，其中的水会形成水滴，太重足以克服吸引它的表面张力，就会流走;但如果空隙够小，水会像薄膜一样，太轻无法克服表面张力，从而稳稳地附着在空隙表面上。
文章逐句翻译
第一段：
Groundwater is the word used to describe water that saturates the ground, filling all the available spaces.
地下水是指渗入地下并填满岩石空隙的水。
By far the most abundant type of groundwater is meteoric water; this is the groundwater that circulates as part of the water cycle.
至今为止最丰富的地下水来源便是气象水，它是自然界水循环的一部分。
Ordinary meteoric water is water that has soaked into the ground from the surface, from precipitation (rain and snow) and from lakes and streams.
普通气象水会从地表、雨雪湖泊和河川渗入地下。
There it remains, sometimes for long periods, before emerging at the surface again.
有时它们会长时间滞留于此，之后再次涌出地表。
At first thought it seems incredible that there can be enough space in the “solid” ground underfoot to hold all this water.
或许在人们看来，坚硬的地壳居然有充足空间来储存这样多的水是难以置信的。
第二段：
The necessary space is there, however, in many forms.
然而，地下水的储存空间是多种多样的。
The commonest spaces are those among the particles—sand grains and tiny pebbles—of loose, unconsolidated sand and gravel.
最常见的便是疏松砂石中的细小颗粒----如沙粒和小鹅卵石----之间的空隙。
Beds of this material, out of sight beneath the soil, are common. They are found wherever fast rivers carrying loads of coarse sediment once flowed.
这些砂石床藏匿于土壤之下，极为普遍，凡是那些负载着粗糙沉积物的湍急河流流经之处都可以发现它们的踪迹。
For example, as the great ice sheets that covered North America during the last ice age steadily
melted away, huge volumes of water flowed from them.
比如，随着冰河时代覆盖北美的巨大冰层逐渐融化，大量融水汹涌流出。
The water was always laden with pebbles, gravel, and sand, known as glacial outwash, that was deposited as the flow slowed down.
水中会携带鹅卵石、砾石和沙石，即所谓的冰水沉积物，它们会随水流渐缓而缓慢沉淀。
第三段：
The same thing happens to this day, though on a smaller scale,
类似事件如今也时常发生，不过规模相对较小罢了。
wherever a sediment-laden river or stream emerges from a mountain valley onto relatively flat land, dropping its load as the current slows: the water usually spreads out fanwise, depositing the sediment in the form of a smooth, fan-shaped slope.
当携带沉积物的河流或溪水从山谷而下，流至相对平坦的地面时，砂石便随着流速减慢而逐渐沉淀：水流通常呈扇形蔓延，进而使所承载的砂石以光滑扇形的斜面形式沉积下来。Sediments are also dropped where a river slows on entering a lake or the sea, the deposited sediments are on a lake floor or the seafloor at first, but will be located inland at some future date, when the sea level falls or the land rises; such beds are sometimes thousands of meters thick.
当河流汇入湖泊和海洋时也会留下沉积物，这些沉淀物最初附着在湖底或海底，但日后一旦海平面下降或者陆地崛起，它们便会分布至内陆，厚度通常达几千米。
第四段：
In lowland country almost any spot on the ground may overlie what was once the bed of a river that has since become buried by soil;
在低地国家，任何一寸土地之下都可能存在曾经河流的河床，这些河流被土壤掩埋而消失。
if they are now below the water’s upper surface (the water table), the gravels and sands of the former riverbed, and its sandbars, will be saturated with groundwater.
如果这些河床如今正位于地下水位之下，那麽其所含的沙石定会储存了大量地下水。
第五段：
So much for unconsolidated sediments. Consolidated (or cemented) sediments, too, contain millions of minute water-holding pores.
上述内容都是有关松散沉积物的储水状况，而坚固沉积物同样也拥有以数万计的微孔来容纳水分。
This is because the gaps among the original grains are often not totally plugged with cementing chemicals;
这是由于最初沙粒的缝隙通常并没有被胶黏质的化学物质完全阻塞，
also, parts of the original grains may become dissolved by percolating groundwater, either while consolidation is taking place or at any time afterwards.
同时，部分颗粒很可能在固化或者固化之后被渗透而下的地下水溶解。
The result is that sandstone, for example, can be as porous as the loose sand from which it was formed.
最终，如由散沙形成的砂岩甚至会变得和散沙一样多孔。
第六段：
Thus a proportion of the total volume of any sediment, loose or cemented, consists of empty space. 因此，无论沉积物属于疏松或是坚固，其整体中必有一部分为真空区。
Most crystalline rocks are much more solid; a common exception is basalt, a form of solidified volcanic lava, which is sometimes full of tiny bubbles that make it very porous.
大部分岩石晶体都非常坚硬，不过也有例外，如玄武岩。它是一种固化的火山熔岩，内部经常充满微小气泡，从而变得十分多孔。
第七段：
The proportion of empty space in a rock is known as its porosity.
岩石真空区比例的大小被称为多孔性。
But note that porosity is not the same as permeability, which measures the ease with which water can flow through a material; this depends on the sizes of the individual cavities and the crevices linking them.
但注意，多孔性与渗透性是不同概念。渗透性衡量的是水渗透物质的难易程度，它取决于物质中独立孔洞以及连接孔洞的裂缝的大小。
第八段
Much of the water in a sample of water-saturated sediment or rock will drain from it if the sample is put in a suitable dry place.
当浸满水分的沉淀物或者岩石样本被放在适宜的干燥环境中时，大部分水分会蒸发。
But some will remain, clinging to all solid surfaces.
但仍有部分水分会继续附着在样本的表面。
It is held there by the force of surface tension without which water would drain instantly from any wet surface, leaving it totally dry.
这是由于水的表面张力使水分得以存留，否则样本将迅速完全干燥。
The total volume of water in the saturated sample must therefore be thought of as consisting of water that can, and water that cannot, drain away.
因此，试验样本的含水量包含两部分，可被蒸发的水和不可被蒸发的水。
第九段：
The relative amount of these two kinds of water varies greatly from one kind of rock or sediment to another, even though their porosities may be the same. What happens depends on pore size.
这两种水分的相对含量因岩石与沉积物种类不同而不同，即便它们的孔隙度相同也是如此。毛孔的大小决定了它们的比例。
If the pores are large, the water in them will exist as drops too heavy for surface tension to hold, and it will drain away;
如果毛孔很大，毛孔中的水会形成过重的水滴，进而可以克服表面张力，从而掉落。
but if the pores are small enough, the water in them will exist as thin films, too light to overcome the force of surface tension holding them in place; then the water will be firmly held.
但如果毛孔足够小，其中的水会像薄膜一样，由于过轻而无法克服吸引它的表面张力，从而被稳固的吸附在孔隙中。
答案及题目解析
Key:
1. C 2. C 3. B 4. D 5. D 6. A 7. A 8. A 9. C 10.B 11.D 12. A 13. D 14. 1 2 3
题目解析：
1. Which of the following can be inferred from paragraph 1 about the ground that we walk on? (Inference Question)
A.It cannot hold rainwater for long periods of time.
B.It prevents most groundwater from circulating.
C.It has the capacity to store large amounts of water.
D.It absorbs most of the water it contains from rivers.
相关原句：At first thought it seems incredible that there can be enough space in the “solid” ground underfoot to hold all this water. (Paragraph 1)
本题解析：文中指出地下居然能储存这麽多水是不可思议的，也就是说地下可以存储大量水，因此选择C。
正确答案：C
2. The word “incredible” in the passage is closest in meaning to (Vocabulary Question)
A.Confusing
B.Comforting
C.Unbelievable
D.Interesting
相关原句：At first thought it seems incredible that there can be enough space in the “solid” ground underfoot to hold all this water. (Paragraph 1)
本题解析：incredible意为“不可思议的”，即“难以相信的(unbelievable)”，因此选择C。
正确答案：C
3. The word “out of sight” in the passage is closest in meaning to (Vocabulary Question)
A.Far away
B.Hidden
C.Partly visible
D.Discovered
相关原句：Beds of this material, out of sight beneath the soil, are common.(Paragraph 2)
本题解析：Out of sight意为“看不见的”，文中指被土壤掩盖了的，即“藏起来的(hidden)”，因此选择B。
正确答案：B
4. According to paragraph 2, where is groundwater usually found? (Factual Information Question)
A.Inside pieces of sand and gravel
B.On top of beds of rock
C.In fast rivers that are flowing beneath the soil
D.In spaces between pieces of sediment
相关原句：The commonest spaces are those among the particles—sand grains and tiny pebbles—of loose, unconsolidated sand and gravel. (Paragraph 2)
本题解析：第二段指出最普遍的地下水存储空间在于疏松土壤和沙石间的空隙，因此选择D。
正确答案：D
5. The phrase “glacial outwash” in the passage refers to (Reference Question)
A.Fast rivers
B.Glaciers
C.The huge volumes of water created by glacial melting
D.The particles carried in water from melting glaciers
相关原句：The water was always laden with pebbles, gravel, and sand, known as glacial outwash, that was deposited as the flow slowed down. (Paragraph 2)
本题解析：“glacial outwash”指的即是河水所承载的鹅卵石、沙石和沙子等，因此选择D。
正确答案：D
6. All of the following are mentioned in paragraph 3 as places that sediment-laden rivers can deposit their sediments EXCEPT(Negative Factual Information Question)
A.A mountain valley
B.Flat land
C.A lake floor
D.The seafloor
相关原句：…wherever a sediment-laden river or stream emerges from a mountain valley onto relatively flat land, dropping its load as the current slows…(Paragraph 3)
Sediments are also dropped where a river slows on entering a lake or the sea, the deposited sediments are on a lake floor or the seafloor at first…(Paragraph 3)
本题解析：本段指出了三处沉积物沉淀的地点：平地(flat land)，湖床(a lake floor)，海床(the seafloor)。山谷(mountain valley)是沉淀物的来源地，不是沉淀地点，因此选择A。
正确答案：A
7. The word “overlie” in the passage is closest in meaning to (Vocabulary Question)
A.Cover
B.Change
C.Separate
D.Surround
相关原句：In lowland country almost any spot on the ground may overlie what was once the bed of a river that has since become buried by soil;(Paragraph 4)
本题解析：overlie意为“叠加、覆盖”，与cover同义，因此选择A。
正确答案：A
8. The phrase “so much for” in the passage is closest in meaning to(Vocabulary Question)
A.That is enough about
B.Now let us turn to
C.Of greater concern are
D.This is related to
相关原句：So much for unconsolidated sediments.(Paragraph 5)
本题解析：so much for意为“暂时说这些…”，文章接下来要讲述有关consolidated sediments，因此关于上文中的疏松沉淀物暂时谈这些。因此选择A。
正确答案：A
9. The word “plugged” in the passage is closet in meaning to (Vocabulary Question)
A.Washed
B.Dragged
C.Filled up
D.Soaked through
相关原句： This is because the gaps among the original grains are often not totally plugged with cementing chemicals; (Paragraph 5)
本题解析：plug意为“塞住”，指沙石缝隙被“填塞住(fill up)”，因此选择C。
正确答案：C
10. According to paragraphs 6 and 7, why is basalt unlike most crystalline forms of rock? (Factual Information Question)
A.It is unusually solid
B.It often has high porosity.
C.It has a low proportion of empty space.
D.It is highly permeable.
相关原句：Most crystalline rocks are much more solid; a common exception is basalt, a form of solidified volcanic lava, which is sometimes full of tiny bubbles that make it very porous.(Paragraph 6)
本题解析：大多数结晶岩石都很坚硬，而玄武岩不同，它具有很多气孔(very porous)，因此选择B。
正确答案：B
11. What is the main purpose of paragraph 7? (Rhetorical Purpose Question)
A.To explain why water can flow through rock
B.To emphasize the large amount of empty space in all rock
C.To point out that a rock cannot be both porous and permeable
D.To distinguish between two related properties of rock
相关原句：But note that porosity is not the same as permeability…(Paragraph 7)
本题解析：本段主要对多孔性和可渗透性这两个岩石的性质做了区别，因此选择D。
正确答案：D
12. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? (Sentence Simplification Question)
A.Surface tension is not strong enough to retain drops of water in rocks with large pores but it strong enough to hold on to thin films of water in rocks with small pores.
B.Water in rocks is held in place by large pores and drains away from small size pores through surface tension.
C.Small pores and large pores both interact with surface tension to determine whether a rock will hold water as heavy drops or as a thin film.
D.If the force of surface tension is too weak to hold water in place as heavy drops, the water will continue to be held firmly in place as a thin film when large pores exist.
相关原句：If the pores are large, the water in them will exist as drops too heavy for surface tension to hold, and it will drain away; but if the pores are small enough, the water in them will exist as thin films, too light to overcome the force of surface tension holding them in place; then the water will be firmly held.(Paragraph 9)
本题解析：本句指出：如果孔大，其中的水会变为水滴，水滴太沉，岩石表面张力握不住，水便会排出;但如果孔足够小，其中的水会变成薄膜，薄膜很轻，无法挣脱表面张力的控制，这样水便会被紧紧收住。因此选择A。
注意：C选项错误在于：并不是孔与张力相互作用，而应是水与张力相互作用。
正确答案：A
13. Look at the four squares [ █ ] that indicate where the following sentence could be added to the passage. (Insert Text Question)
What, then, determines what proportion of the water stays and what proportion drains away?
Where would the sentence best fit? Click on a square to add the sentence to the passage.
Much of the water in a sample of water-saturated sediment or rock will drain from it if the sample is put in a suitable dry place.█(A)But some will remain, clinging to all solid surfaces.█(B) It is held there by the force of surface tension without which water would drain instantly from any wet surface, leaving it totally dry.█(C) The total volume of water in the saturated sample must therefore be thought of as consisting of water that can, and water that cannot, drain away.█(D)What, then, determines what proportion of the water stays and what proportion drains away?
本题解析：插入句中“what proportion of the water stays ”与“ what proportion drains away”暗示着其前一句必有关于两种水份的存在的内容，而原段末句恰总结了岩石中所含种水份“water that can and water that cannot drain away”，因此选择D。
正确答案：D
14. Directions: An introductory sentence for a brief summary of the passage is provided below. Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage. Some sentences do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage. This question is worth 2 points. (Prose Summary Question)
Much of the ground is actually saturated with water.
●
●
●
Answer choices
1.Sediments that hold water were spread by glaciers and are still spread by rivers and streams. (√)
2.Water is stored underground in beds of loose sand and gravel or in cemented sediment. (√)
3.The size of a saturated rock’s pores determines how much water it will retain when the rock is put in a dry place. (√)
4.Groundwater often remains underground for a long time before it emerges again.
5.Like sandstone, basalt is a crystalline rock that is very porous.
6.Beds of unconsolidated sediments are typically located at inland sites that were once underwater.
本题解析：正确答案应陈述文章主要内容----承载地下水的物质(疏松沉淀物和非疏松沙石)以及其吸附水份的空间。
1.选项内容指出了疏松沉淀物来自于冰川或河流的扩展，文中二三两段中描述了冰川和如今的河流如何将承载的疏松物质沉淀下来，1正确。
2.选项内容总结了地下水储存的两种物质：疏松沉积物和非疏松沙石，2正确。
3.选项内容指出了地下蓄水岩石的孔大小决定了水份被排除还是被保留，末端总结了这一内容：孔大则水排出，孔小则水储存，3正确。
4.属细节内容，4错误。
5.属细节内容，5错误。
6.文中指出非疏松沉积物后来有可能位移至内陆，但并未说明内陆曾经有地下水(were once underwater)，6错误。
正确答案：
1，2，3
段意及难句解析：
●第一段：
段意：
讲述何为地下水以及其最主要的形式之一：气象水。
难句分析：
1.Ordinary meteoric water is water that has soaked into the ground from the surface, from precipitation (rain and snow) and from lakes and streams.
短语：soak into：渗入
主干：Ordinary meteoric water is water that has soaked into the ground…
释义：普通气象水是那些通过地表，从降水和河流渗入到地下的水分。
2. There it remains, sometimes for long periods, before emerging at the surface again. At first
thought it seems incredible that there can be enough space in the “solid” ground underfoot to hold all this water.
短语：at first thought：起初看来
分句：there it remains before emerging at the surface again：指在重新涌出地表之前，气象水会存留(remains)在地下
it seems incredible that…：…看上去是不可思议的
释义：在重新涌出地表之前，有时候有相当长一段时间，地下水都会存于地下。然而起初看来，坚硬的地面下居然能有足够空间容纳这麽多水是不可思议的。
●第二段：
段意：
指出承载地下水的空间有很多形式，其中最普通的一种便是地下疏松沙石层的颗粒间的空隙。接着描述了这种疏松沙石层的形成。
难句分析：
1. The commonest spaces are those among the particles—sand grains and tiny pebbles—of loose, unconsolidated sand and gravel.
分句：particles of loose, unconsolidated sand and gravel：疏松沙石的颗粒(如沙粒和小鹅卵石：sand grains and tiny pebbles)
释义：最普通的一种空隙存在于疏松而不坚实的沙石中的颗粒----沙粒和小鹅卵石----之间。
2. They are found wherever fast rivers carrying loads of coarse sediment once flowed.
短语：coarse sediment once flowed：曾经漂流的粗糙沉淀物
loads of：一载载的，一堆堆的
释义：只要哪里有湍急的河流载着粗糙的曾经漂流的沉淀物，哪里就能发现这种物质层。
3. The water was always laden with pebbles, gravel, and sand, known as glacial outwash, that was deposited as the flow slowed down.
短语：be laden with：负载着…
pebbles, gravel, and sand, known as glacial outwash：指冰水沉积物包括鹅卵石、碎石和沙子
分句：that was deposited as the flow slowed down：随着水流渐缓而沉积下来
释义：融化的水总是载着被称为冰水沉积物的鹅卵石、碎石和沙子，它们随着水流渐缓而沉
积下来。
●第三段：
段意：
讲述如今这种疏松沙石层的形成，或沉积于平原，或沉积于河流入海口。
难句分析：
1. The same thing happens to this day, though on a smaller scale, wherever a sediment-laden river or stream emerges from a mountain valley onto relatively flat land, dropping its load as the current slows: the water usually spreads out fanwise, depositing the sediment in the form of a smooth, fan-shaped slope.
短语：a sediment-laden river or stream：载满沉积物的河流或小溪
emerge from…onto：从…发源，流至…
spreads out：向四周展开
in the form of：以…的形式
a smooth, fan-shaped slope：光滑的扇形斜面
释义：如今也发生着同样的事情，虽然规模较小。有满载沉淀物的河流或小溪从山谷出发向下蔓延到相对平坦的地面，当水流渐缓时便将沉淀物留下：河水通常呈扇形展开，将沉淀物以光滑的扇形斜面形式沉积下来。
2. Sediments are also dropped where a river slows on entering a lake or the sea, the deposited sediments are on a lake floor or the seafloor at first, but will be located inland at some future date, when the sea level falls or the land rises; such beds are sometimes thousands of meters thick.
分句：where a river slows on entering a lake or the sea：指河流在入湖或海(on entering a lake or sea)时流速减缓
主干：sediments are also dropped where…,the deposited sediments are on…,but will be located…,when…;such beds are thousands of meters thick
释义：当河流接近湖泊或海洋时沉淀物也会被沉积下，沉积物起初会存在于湖床或海床，但随着未来当海平面下降或陆地上升时，沉积物便会移动到内陆去;这些沉积物层(such beds)有时有数千米厚。
●第四段：
段意：
讲述沉积物层的最终形成：如果在水平面下，其所含的沙石就会被地下水浸透。
难句分析：
In lowland country almost any spot on the ground may overlie what was once the bed of a river that has since become buried by soil;
分句：any spot on the ground：地面上任何一点
what was once the bed of a river：河流曾经的河床地带，作may overlie的宾语
a river that has since become buried by soil：已经被土壤所掩埋的河流
释义：在低地国家，几乎地面上任何一点都有可能叠加在被土壤掩埋的河流的河床上。
●第五段：
段意：
讲述非疏松沉积物如何也能储藏地下水：它们也存在空隙。
难句分析：
This is because the gaps among the original grains are often not totally plugged with cementing chemicals; also, parts of the original grains may become dissolved by percolating groundwater, either while consolidation is taking place or at any time afterwards.
短语：be plugged with：被…塞住
cementing chemicals：胶黏性化学物质
become dissolved by：被…所溶解
释义：这是因为原始沙石间的缝隙通常并未被胶黏的化学物质完全填塞;同时，部分原始沙石有可能被渗透下来的地下水溶解，溶解过程无论是在沙石坚化发生之时还是以后的某一时期都会进行。
●第六段：
段意：
总结无论是疏松的还是粘结的沉积物都具有空隙。
难句分析：
Most crystalline rocks are much more solid; a common exception is basalt, a form of solidified volcanic lava, which is sometimes full of tiny bubbles that make it very porous.
短语：solidified volcanic lava：硬化后的火山岩浆
释义：大多数结晶岩石更加坚硬;一个典型例外是玄武岩，一种硬化了的火山岩浆形式，它有时充满了小气泡，这使它非常多孔。
●第七段：
段意：
本段主要对多孔性和可渗透性做了区别。
难句分析：
But note that porosity is not the same as permeability, which measures the ease with which water can flow through a material; this depends on the sizes of the individual cavities and the crevices linking them.
分句：“the ease with which water can flow through a material”：指水通过某一物质的容易程度
cavities and the crevices linking them：连接沙石的空隙和裂缝
释义：但需注意多孔性不同于可渗透性。可渗透性丈量的是水流通过某一物质的容易程度，它取决于连接沙石的单个空隙和裂缝的大小。
●第八段：
段意：
本段将浸水的沉积物样本中所含的水分为可排出和不可排出两部分。
难句分析：
The total volume of water in the saturated sample must therefore be thought of as consisting of water that can, and water that cannot, drain away.
短语：be thought of as：被认为是…
释义：因此，浸水样本所含的所有水份必须被分为两部分：可排除的与不可排除的。
●第九段：
段意：
本段指出不同岩石中两种水份的含量大为不同，这取决于岩石的多孔性。
难句分析：
If the pores are large, the water in them will exist as drops too heavy for surface tension to hold, and it will drain away; but if the pores are small enough, the water in them will exist as thin films, too light to overcome the force of surface tension holding them in place; then the water will be firmly held.
分句：drops (that are) too heavy for surface tension to hold：由于过重而导致岩石表面张力无法收控住的水滴
surface tension holding them in place：将(水滴)收控住的表面张力
…thin films, too light to overcome the force of surface tension：薄膜过轻，无法挣脱张力的控制
主干：If the pores are large,the water will exsit as … and will drain away;but if the pores are small enough,the water will exsit as…,then will be held
释义：如果孔大，其中的水会变为水滴，水滴太沉，表面张力握不住，水便会排出;但如果孔足够小，其中的水会变成薄膜，薄膜很轻，无法挣脱表面张力的控制，这样水便会被紧紧收住。
