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.
If the pores are large,the water will exist as (too heavy for surface tension to hold)drops,and it will drain away;but if the pores are small enough,the water will exist as (too light to overcome the force of (holding them in place)surface tension )thin films;then the water will be (firmly )held.
翻译：如果微孔是大的，那么在这些微孔中的水是作为（对于表面张力来说太重的）水滴存在的，并且这些水将会流走；但是如果微孔足够小，那么这些微孔中的水是作为（太轻而无法克服（支撑它们在此处的）表面张力的）薄膜存在的,然后这些水将被坚实的支撑住。
有一个让步关系，一个强另一个弱。
Which of sentences below best expression the essential information in the highlighted sentence in the passage?Incorrect choices change the meaning in important ways or leave out essential information.
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Surface tension is not strong enough to retain drops of water in rocks with large pores but is strong enough to hold on to thin films of water in rocks with small pores.
Surface tension is not strong enough to retain (of (in (with large pores)rocks)water)drops but Surface tension is strong enough to hold on to ( of (in (with small pores)rocks)water )thin films.
表面张力不足以保留（在大孔岩石间的）水滴，但是表面张力足够支撑（在小孔岩石间的）薄膜。
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Water in rocks is held in place by large pores and drains away from small size pores through surface tensions
(in rocks)Water is held in (by large pores and (away from (small size)+(through surface tensions) pores )drains )place .
（石头间的）水被保持在这些（有大微孔和（小型的且穿过表面张力的）水滴的）地方。
---并没有大微孔。
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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.
Small pores and large pores both interact with(to determine whether a rock will hold ( as heavy drops or as a thin film)water) surface tension .
小孔和大孔在（去决定是否一个石头可以支持住（像重水珠的或者像薄膜的）水的）表面张力的作用下相互作用。
--没有大孔
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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.
If the (of surface tension) force is too weak to hold (in place as heavy drops)water ,the (in place as a thin film )water will continue to be held firmly (when large pores exist).
如果（表面的）力量太小不足以支撑（在那里像大水滴一样的）水，这个（在那里像薄膜一样的）水将会持续坚实的（当大微孔出现时）保持。
----关系错误，不是条件关系是让步关系
