例246　A 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.

【结构分析】这是个明显的转折句，whereas前面的句子的主干是A rather similar process of differentiation has led to professional geologists，后面是分词定语修饰前面的名词geologists，也就是coming together nationally within one or two specific societies, whereas后面是个either...or...引导的并列句，第一个并列句是the amateurs have tended to remain in local societies，第二个并列句是to come together nationally in a different way。

【亮点回放】此句话的亮点是个超级转折句，后半部分的转折句采用了either...or...，很精彩。

【核心词汇】

a rather similar process of differentiation　一个颇为相似的分化过程

professional geologists　专业的地质学家

specific societies　专科学术社团

whereas　然而

the amateurs　业余地质爱好者

remain in local societies　留在地方社团

【参考译文】一个颇为相似的分化过程已经导致专业的地质学家走到一起组成一到两个全国性的专科学术社团，而业余地质爱好者们倾向于要么仍留在地方社团，要么也以另一种方式组成全国性机构。