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31. Studies by Hargrave and Geen estimated natural community grazing rates by measuring feeding rates ofindividual zooplankton species in thelaboratory and then computing community grazing rates for field conditionsusing the known population densityof grazers. (5)
由哈格雷夫(Hargrave)和吉恩(Geen)所進行的研究，對自然條件下的群落捕食速率進行了估計，其手段是通過測量出實驗室內(nèi)單獨的浮游動物種類的捕食速率，然后利用已知的食草動物種群密度，計算出實地狀況下的群落捕食速率。
難句類型：復雜修飾
解釋：本句對閱讀者的閱讀能力提出了更高的要求，不但要求讀者讀清楚句子的復雜的結(jié)構(gòu)，而且對讀者的詞匯能力也提出了更高的要求。
By以前結(jié)構(gòu)無需解釋，by以后有兩個作介詞賓語短語的動名詞結(jié)構(gòu)，measuring和后面表示并列和順接的and then之后的computing，說的是計算方法;前一個measuring說的是先算出實驗室中浮游動物品種的單位捕食速率，后面的computing前其實省略了一個by，而且在這個動名詞結(jié)構(gòu)中還包括一個分詞結(jié)構(gòu)using the known population density of grazers，用已知的捕食者的種群密度計算出其野外的群體捕食速率。整個的by以后的計算過程簡單了就是：實驗室單位速率×野外密度=野外群體速率
另外本句中的詞匯也頗有迷惑性;雖然沒有太難的單詞，但是很多單詞都是同義詞和反義詞，容易讓人讀混;(斜線分隔同義詞，冒號分隔反義詞)
estimate/measure/compute; feeding rates/grazing rates; zooplankton/grazers; natureal/field; laboratory community; individuall
意群訓練：Studies by Hargrave and Geen estimated natural community graz-ing rates by measuring feeding rates ofindividual zooplankton species in thelaboratory and then computing community grazing rates for field conditionsusing the known population densityof grazers.
32. In the periodsof peak zooplankton abundance，that is，in the late spring and in the summer，Haney recorded maximum daily community grazing rates，for nutrient-poorlakes and bog lakes，respectively，of 6.6 percent and 114 percent of daily phytoplankton production. (3+)
在浮游動物數(shù)量激增的高峰期，亦即在春季后期以及夏季，哈尼記錄了最大程度上的每日群落食草比率，對于營養(yǎng)物不充足的湖和沼澤湖而言，分別為每日浮游植物繁殖量的6.6%和114%.
難句類型：插入語
解釋：句中有兩組插入語，每組兩個插入語，尤其是第二組，把rate of從中間劈開。不過因為句義尚好理解，所以本句只是有一點別扭，但不算太難。
意群訓練：In the periodsof peak zooplankton abundance，that is，in the late spring and in the summer，Haney recorded maximum daily community grazing rates，for nutrient-poorlakes and bog lakes，respectively，of 6.6 percent and 114 percent of daily phytoplankton production.
33. The hydrologic cycle，a major topic in this science，is the complete cycle of phenomena through which water passes，beginning as atmospheric water vapor，passing into liquid and solid form as precipitation，thence along and into the ground surface，and finally again returning to the form of atmospheric water vapor by means of evaporation and transpiration. (4)
水文循環(huán)(hydrologic cycle)，作為該學科中的一個主要課題，指的是水所經(jīng)過的諸現(xiàn)象的整個循環(huán)過程，開始時是作為大氣中的水蒸氣，轉(zhuǎn)而作為雨、雪、露、雹一類的降水量經(jīng)過液體和固體形態(tài)，由此而沿著地層表面分布或進入地層表面，最終通過蒸發(fā)和散發(fā)作用再度回復到大氣水蒸氣的形態(tài)。
難句類型：復雜修飾、插入語、省略
水文循環(huán)(hydrologic cycle)，作為該學科中的一個主要課題，指的是水所經(jīng)過的諸現(xiàn)象的整個循環(huán)過程，開始時是作為大氣中的水蒸氣，轉(zhuǎn)而作為雨、雪、露、雹一類的降水量經(jīng)過液體和固體形態(tài)，由此而沿著地層表面分布或進入地層表面，最終通過蒸發(fā)和散發(fā)作用再度回復到大氣水蒸氣的形態(tài)。
解釋：beginning開始的一系列分詞都是修飾主語The hydrologic cycle的，分別是beginning/passing/passing/returning。值得注意的是，thence along and into the grund surfacee 是thence passing along and entering into the ground surfacee的省略形式，但是看上去意思卻很清楚。類似這樣的省略，是出題者合理地利用了省略來達到改編學術(shù)論文時壓縮文章篇幅的目的。
意群訓練：The hydrologic cycle，a major topic in this science，is the complete cycle of phenomena through which water passes，beginning as atmospheric water vapor，passing into liquid and solid form as precipitation，thence along and into the ground surface，and finally again returning to the form of atmospheric water vapor by means of evaporation and transpiration.
34. Only when a system possesses natural or artificial boundaries that associate the water within it the hydrologic cycle may the entire system properly be termed hydrogeologic.(4) 感謝您閱讀《歷年GRE閱讀材料難句精選100句(四) 》一文，出國留學網(wǎng)(liuxue86.com)編輯部希望本文能幫助到您。
31. Studies by Hargrave and Geen estimated natural community grazing rates by measuring feeding rates ofindividual zooplankton species in thelaboratory and then computing community grazing rates for field conditionsusing the known population densityof grazers. (5)
由哈格雷夫(Hargrave)和吉恩(Geen)所進行的研究，對自然條件下的群落捕食速率進行了估計，其手段是通過測量出實驗室內(nèi)單獨的浮游動物種類的捕食速率，然后利用已知的食草動物種群密度，計算出實地狀況下的群落捕食速率。
難句類型：復雜修飾
解釋：本句對閱讀者的閱讀能力提出了更高的要求，不但要求讀者讀清楚句子的復雜的結(jié)構(gòu)，而且對讀者的詞匯能力也提出了更高的要求。
By以前結(jié)構(gòu)無需解釋，by以后有兩個作介詞賓語短語的動名詞結(jié)構(gòu)，measuring和后面表示并列和順接的and then之后的computing，說的是計算方法;前一個measuring說的是先算出實驗室中浮游動物品種的單位捕食速率，后面的computing前其實省略了一個by，而且在這個動名詞結(jié)構(gòu)中還包括一個分詞結(jié)構(gòu)using the known population density of grazers，用已知的捕食者的種群密度計算出其野外的群體捕食速率。整個的by以后的計算過程簡單了就是：實驗室單位速率×野外密度=野外群體速率
另外本句中的詞匯也頗有迷惑性;雖然沒有太難的單詞，但是很多單詞都是同義詞和反義詞，容易讓人讀混;(斜線分隔同義詞，冒號分隔反義詞)
estimate/measure/compute; feeding rates/grazing rates; zooplankton/grazers; natureal/field; laboratory community; individuall
意群訓練：Studies by Hargrave and Geen estimated natural community graz-ing rates by measuring feeding rates ofindividual zooplankton species in thelaboratory and then computing community grazing rates for field conditionsusing the known population densityof grazers.
32. In the periodsof peak zooplankton abundance，that is，in the late spring and in the summer，Haney recorded maximum daily community grazing rates，for nutrient-poorlakes and bog lakes，respectively，of 6.6 percent and 114 percent of daily phytoplankton production. (3+)
在浮游動物數(shù)量激增的高峰期，亦即在春季后期以及夏季，哈尼記錄了最大程度上的每日群落食草比率，對于營養(yǎng)物不充足的湖和沼澤湖而言，分別為每日浮游植物繁殖量的6.6%和114%.
難句類型：插入語
解釋：句中有兩組插入語，每組兩個插入語，尤其是第二組，把rate of從中間劈開。不過因為句義尚好理解，所以本句只是有一點別扭，但不算太難。
意群訓練：In the periodsof peak zooplankton abundance，that is，in the late spring and in the summer，Haney recorded maximum daily community grazing rates，for nutrient-poorlakes and bog lakes，respectively，of 6.6 percent and 114 percent of daily phytoplankton production.
33. The hydrologic cycle，a major topic in this science，is the complete cycle of phenomena through which water passes，beginning as atmospheric water vapor，passing into liquid and solid form as precipitation，thence along and into the ground surface，and finally again returning to the form of atmospheric water vapor by means of evaporation and transpiration. (4)
水文循環(huán)(hydrologic cycle)，作為該學科中的一個主要課題，指的是水所經(jīng)過的諸現(xiàn)象的整個循環(huán)過程，開始時是作為大氣中的水蒸氣，轉(zhuǎn)而作為雨、雪、露、雹一類的降水量經(jīng)過液體和固體形態(tài)，由此而沿著地層表面分布或進入地層表面，最終通過蒸發(fā)和散發(fā)作用再度回復到大氣水蒸氣的形態(tài)。
難句類型：復雜修飾、插入語、省略
水文循環(huán)(hydrologic cycle)，作為該學科中的一個主要課題，指的是水所經(jīng)過的諸現(xiàn)象的整個循環(huán)過程，開始時是作為大氣中的水蒸氣，轉(zhuǎn)而作為雨、雪、露、雹一類的降水量經(jīng)過液體和固體形態(tài)，由此而沿著地層表面分布或進入地層表面，最終通過蒸發(fā)和散發(fā)作用再度回復到大氣水蒸氣的形態(tài)。
解釋：beginning開始的一系列分詞都是修飾主語The hydrologic cycle的，分別是beginning/passing/passing/returning。值得注意的是，thence along and into the grund surfacee 是thence passing along and entering into the ground surfacee的省略形式，但是看上去意思卻很清楚。類似這樣的省略，是出題者合理地利用了省略來達到改編學術(shù)論文時壓縮文章篇幅的目的。
意群訓練：The hydrologic cycle，a major topic in this science，is the complete cycle of phenomena through which water passes，beginning as atmospheric water vapor，passing into liquid and solid form as precipitation，thence along and into the ground surface，and finally again returning to the form of atmospheric water vapor by means of evaporation and transpiration.
34. Only when a system possesses natural or artificial boundaries that associate the water within it the hydrologic cycle may the entire system properly be termed hydrogeologic.(4) 感謝您閱讀《歷年GRE閱讀材料難句精選100句(四) 》一文，出國留學網(wǎng)(liuxue86.com)編輯部希望本文能幫助到您。