難句解析：
①No clear-cut distinction can be drawn between professionals and amateurs in science: exceptions can be found to any rule. Nevertheless, the word "amateur" does carry a connotation that the person concerned is not fully integrated into the scientific community and, in particular, may not fully share its values.
▲先看前面的句子的主干是No... distinction can be drawn between...，冒號(hào)后面的內(nèi)容是進(jìn)一步說(shuō)明前面的觀點(diǎn)。在第二個(gè)句子中，一上來(lái)就有一個(gè)轉(zhuǎn)折詞nevertheless，表示語(yǔ)意的轉(zhuǎn)折，其主句是the word "amateur" does carry a connotation，后面有一個(gè)同位語(yǔ)從句，里面有兩個(gè)并列謂語(yǔ)。
△注意nevertheless表示轉(zhuǎn)折，其后的信息與其前面的信息意思相反，前面講二者沒(méi)有很明顯的區(qū)別，后面便說(shuō)業(yè)余和專業(yè)就是不一樣。其次要看清the word "amateur" DOES carry a connotation而非DOES NOT。
②The trend was naturally most obvious in those areas of science based especially on a mathematical or laboratory training, and can be illustrated in terms of the development of geology in the United Kingdom.
▲兩個(gè)分句有同一個(gè)主語(yǔ)，即the trend，兩個(gè)謂語(yǔ)為was obvious和can be illustrated。前一個(gè)分句中based especially on a mathematical or laboratory training修飾areas of science。
△注意be illustrated的用法，這里是“舉例說(shuō)明，例證說(shuō)明”的意思；另外in terms of是“就某事來(lái)說(shuō)，以某事為例”的意思。
③A comparison of British geological publications over the last century and a half reveals not simply an increasing emphasis on the primacy of research, but also a changing definition of what constitutes an acceptable research paper.
▲本句的主語(yǔ)是a comparison of British geological publications over the last century and a half（中心詞為a comparison），謂語(yǔ)是reveals，賓語(yǔ)主體結(jié)構(gòu)是not simply... but also...所連接的兩個(gè)并列賓語(yǔ)，注意賓語(yǔ)emphasis和definition前都有分詞來(lái)修飾。
△an increasing emphasis on the primacy of research譯為“對(duì)科研的重要性的強(qiáng)調(diào)不斷攀升”，a changing definition of what constitutes an acceptable research paper譯為“一篇過(guò)得去的科研論文創(chuàng)作標(biāo)準(zhǔn)也有所變化”，其中what指代the elements that。
④The overall result has been to make entrance to professional geological journals harder for amateurs, a result that has been reinforced by the widespread introduction of refereeing, first by national journals in the nineteenth century and then by several local geological journals in the twentieth century.
▲全句的主干結(jié)構(gòu)是The... result has been to do sth.。注意逗號(hào)后面只是一個(gè)名詞性的短語(yǔ)，其核心詞是a result，可以被看成是前面句子主語(yǔ)的同位語(yǔ)，在其內(nèi)部主要是一個(gè)長(zhǎng)的定語(yǔ)從句，而定語(yǔ)從句中又有兩個(gè)并列的狀語(yǔ)first by..., and then by...。
△entrance入口，此處指發(fā)表文章，進(jìn)入專業(yè)圈子。reinforce增強(qiáng)，也就是使難度更高。本句的理解重點(diǎn)在于理順句子結(jié)構(gòu)，要看到在第一個(gè)逗號(hào)之后沒(méi)有動(dòng)詞了，可以一層一層地把這個(gè)名詞短語(yǔ)分解開(kāi)。
⑤A rather similar process of differentiation has led to professional geologists coming together nationally within one or two specific societies, whereas the amateurs have tended either to remain in local societies or to come together nationally in a different way.
▲這是一個(gè)并列關(guān)系的并列句，兩個(gè)分句由whereas（而）連接，說(shuō)明了兩種情況，前面是在說(shuō)professional，而后面說(shuō)amateurs。
△coming together nationally within one or two specific societies理解為“組成一到兩個(gè)全國(guó)性的專科學(xué)術(shù)社團(tuán)”。
來(lái)源:可可英語(yǔ) http://www.ccdyzl.cn/kaoyan/201405/299823.shtml