TPO2 PASSAGE 1 GRANDWATER
阅读训练方法：
1)朗读直至熟练
2)模仿结构造出自己的句子。
3)复述整个 passage 给同学听，使用你刚刚学到的结构。
4)每天重复这个步骤，你的学科词汇，抽象名词理解，听力理解都不是问题了。
下列句子大部分是整篇文章的出题点，理解这些句子，对于熟悉TPO很重要。
1) At first thought it seemsincredible that there can be enough space in the “solid” ground underfoot tohold all this water. (出题点，注意incredible的语气)
2)The commonest spaces are those among the particles—sand grains andtiny pebbles—of loose, unconsolidated sand and gravel. (插入语的干扰)
3)The same thing happens to this day,though on a smaller scale, wherever a sediment-laden river or stream emergesfrom a mountain valley onto relatively flat land, dropping its load as thecurrent slows: the water usually spreads out fanwise, depositing the sedimentin the form of a smooth, fan-shaped slope. (-doing 做句子状语的语法现象)
4)In lowland country almost any spot onthe ground may overlie what was once the bed of a river that has since becomeburied by soil; (对overlie的理解对于整个句子很重要)
5)This is because the gaps among theoriginal 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. (专有名词和学术话题使得阅读困难)
6)Most crystalline rocks are much moresolid; a common exception is basalt, a form of solidified volcanic lava, whichis sometimes full of tiny bubbles that make it very porous. (注意exception成为出题点)
7)The proportion of empty space in a rock is known as itsporosity. But note that porosity is not the same as permeability, whichmeasures the ease with which water can flow through a material; this depends onthe sizes of the individual cavities and the crevices linking them.(专有名词密集之处成为出题点)
8)The total volume ofwater in the saturated sample must therefore be thought of as consisting ofwater that can, and water that cannot, drain away. ( water that can, and water that cannot的并列信息)
9) If the pores are large, the water in them will exist as drops tooheavy for surface tension to hold, and it will drain away; but if the pores aresmall enough, the water in them will exist as thin films, too light to overcomethe force of surface tension holding them in place; then the water will befirmly held. (信息多，带转折逻辑，句子简化题出处)
