求教&探讨 examine VS explain VS expand在主旨题中的差别

Helenmm

连续错了几道包含examine的主旨题，应该是对examine的理解不准确，诚心赐教！

求教问题：

1、examine在这种主旨题中，一般是指怎样的？/啥情况是对的？（查了词典，说examine指审查检查 带有批判性的看看问题是什么/或者找出问题所在，explain指说明 呈现 使理解使清晰；是不是说examine更多作者主观观点，explain更多作者客观陈述；但是表达作者观点的不一定就是examine，examine带有找问题的目的，不是为了找问题的也可能是别的，比如expand...是从目的出发？）

2、文章主体的叙事内容 VS 文章的purpose 怎么把握？是不是不能从文章主要/大部分在讲的内容来判断主旨？而是从关联？但这种关联好难把握啊....

比如 文章一Anthropologists studying the Hopi people of the southwestern United States often characterize Hopi society between 1680 and 1880 as surprisingly stable, considering that it was a period of diminution in population and pressure from contact with outside groups, factors that might be expected to cause significant changes in Hopi social arrangements.

The Hopis' retention of their distinctive sociocultural system has been attributed to the Hopi religious elite's determined efforts to preserve their religion and way of life, and also to a geographical isolation greater than that of many other Native American groups, an isolation that limited both cultural contact and exposure to European diseases. But equally important to Hopi cultural persistence may have been an inherent flexibility in their social system that may have allowed preservation of traditions even as the Hopis accommodated themselves to change. For example, the system of matrilineal clans was maintained throughout this period, even though some clans merged to form larger groups while others divided into smaller descent groups. Furthermore, although traditionally members of particular Hopi clans appear to have exclusively controlled particular ceremonies, a clan's control of a ceremony might shift to another clan if the first became too small to manage the responsibility. Village leadership positions traditionally restricted to members of one clan might be similarly extended to members of other clans, and women might assume such positions under certain unusual conditions.

主旨：The passage is primarily concerned with

examining the assumptions underlying an interpretation of a phenomenon

expanding on an explanation of a phenomenon

纠结二选一种选了examine，理解为 religious elite's determined efforts和 isolation 是解释为什么stable的 assumptions ，作者examine了，然后说不完整，进行补充

expand扩充，也没有错，但是感觉忽略了前面作者对议题和传统解释的陈述和解释，没有说明expand的目的是什么

文章二

Anole lizard species that occur together (sympatrically) on certain Caribbean islands occupy different habitats: some live only in the grass, some only on tree trunks, and some only on twigs. These species also differ morpho-logically: grass dwellers are slender with long tails, tree dwellers are stocky with long legs, twig dwellers are slender but stubby-legged. What is striking about these lizards is not that coexisting species differ in morphology and habitat use (such differences are common among closely related sympatric species), but that the same three types of habitat specialists occur on each of four islands: Puerto Rico, Cuba, Hispaniola, and Jamaica. Moreover, the Puerto Rican twig species closely resembles the twig species of Cuba, Hispaniola, and Jamaica in morphology, habitat use, and behavior. Likewise, the specialists for other habitats are similar across the islands.

The presence of similar species on different islands could be variously explained. An ancestral species might have adapted to exploit a particular ecological niche on one island and then traveled over water to colonize other islands. Or this ancestral species might have evolved at a time when the islands were connected, which some of these islands may once have been. After the islands separated, the isolated lizard populations would have become distinct species while also retaining their ancestors' niche adaptations. Both of these scenarios imply that specialization to each niche occurred only once. Alternatively, each specialist could have arisen independently on each of the islands.

If each type of specialist evolved just once, then similar specialists on different islands would be closely related. Conversely, if the specialists evolved independently on each island, then a specialist on one island would be more closely related to other types of anoles on the same island-regardless of their ecological niches-than it would be to a similar specialist on a different island.

Biologists can infer how species are related evolutionarily by comparing DNA sequences for the same genes in different species. Species with similar DNA sequences for these genes are generally more closely related to each other than to species with less-similar DNA sequences. DNA evidence concerning the anoles led researchers to conclude that habitat specialists on one island are not closely related to the same habitat specialists elsewhere, indicating that specialists evolved independently on each island.

The primary purpose of the passage is to

explain how researchers resolved a particular scientific question concerning anole lizard species

examine different explanations for a particular trait common to certain anole lizard species

同样纠结二选一选了examine，但结果是explain

文章主体都是在讲现象、不同的解释的可能性、最后科学家盖棺定论 ——如果从文章主体来看，科学家resolve的解释好像就一笔带过了一样，如何判别文章的写作目的是科学家解决这个问题呢？

求教问题：

1、examine在这种主旨题中，一般是指怎样的？/啥情况是对的？（查了词典，说examine指审查检查 带有批判性的看看问题是什么/或者找出问题所在 还有探讨 剖析的意思....explain指说明 呈现 使理解使清晰；是不是说examine更多作者主观观点，explain更多作者客观陈述；但是表达作者观点的不一定就是examine，examine带有找问题的目的，不是为了找问题的也可能是别的，比如expand...是从目的出发？）

2、文章主体的叙事内容 VS 文章的purpose 怎么把握？是不是不能从文章主要/大部分在讲的内容来判断主旨？而是从关联？但这种关联好难把握啊....

谢谢！