GRE Reading Comprehension: Main Idea Questions

Correct a Misconception

The passage states a conventional view, then pivots with 'however' or 'in fact' to argue it is wrong. The main idea is the correction itself. Look for pivot words near the beginning.

Present Multiple Theories

The passage introduces two or more competing explanations for a phenomenon, sometimes favoring one. The main idea is 'discussing different theories about X' — not resolving the debate unless the passage explicitly does so.

Explain a Phenomenon

The passage describes a process, trend, or change and explains the causes or mechanisms behind it. The main idea traces the entire causal chain, not any single link in it.

Qualified Endorsement

The passage describes someone's work positively but criticizes their conclusions. The main idea captures both halves — the value of the evidence and the flaw in the conclusion.

Provide Evidence for a Trend

The passage opens with a broad trend and then dives into a specific case study to substantiate it. The main purpose is to use the example to support the broader claim, not to analyze the example for its own sake.

For decades, transposable elements — segments of DNA capable of copying themselves and inserting into new genomic locations — were dismissed as 'junk DNA,' genomic parasites that persisted solely through their ability to replicate. This characterization, however, has undergone significant revision. Recent research has revealed that a substantial proportion of the regulatory sequences governing mammalian gene expression derive from domesticated transposable elements, a process termed 'exaptation.' In the human genome alone, an estimated 25 percent of promoter regions — the stretches of DNA where transcription is initiated — contain sequences traceable to ancient transposable element insertions.\n\nThe mechanism by which these selfish genetic elements become integrated into the host's regulatory architecture is now better understood, though several aspects remain contentious. When a transposable element inserts near a gene, it may introduce novel transcription factor binding sites. If the binding site happens to confer a regulatory advantage, natural selection can fix the insertion in the population. Over evolutionary timescales, mutations accumulate in the transposable element, rendering it incapable of further transposition while preserving its regulatory function.\n\nCritics of the exaptation model, however, caution against overstating the extent of functional co-option. Lynch and colleagues have argued that many regulatory sequences attributed to transposable elements may have arisen through convergent evolution rather than direct inheritance from a transposon ancestor. Under this alternative view, the regulatory landscape would have evolved similar motifs independently in multiple lineages.\n\nThe debate has practical implications. If the exaptation model is broadly correct, then transposable elements represent a vast reservoir of regulatory innovation. Conversely, if convergent evolution accounts for most of the observed patterns, the focus should shift to understanding the biophysical constraints that channel regulatory evolution. Both perspectives agree, however, that the old conception of transposable elements as mere genomic detritus is no longer tenable.

The systematic study of Old English literature in nineteenth-century Britain was never a purely scholarly enterprise. When pioneering philologists began publishing editions and translations of Anglo-Saxon texts in the 1830s and 1840s, they did so within an intellectual climate that increasingly valued the construction of national origin narratives.\n\nSharon Turner's influential 'History of the Anglo-Saxons' epitomizes this tendency. Turner presented the Anglo-Saxon period as the seedbed of English liberty, drawing parallels between the witenagemot and the modern Parliament. His reading required a selective emphasis on those texts that could be made to prefigure democratic governance, while downplaying evidence of autocratic kingship and widespread unfreedom.\n\nNot all Victorian scholars embraced this instrumentalization of the Anglo-Saxon past. Frederick Furnivall advocated a more empirical approach that prioritized the publication of texts in their original forms. Yet Furnivall's empiricism had its own limitations. His focus on producing accessible editions sometimes led him to standardize orthographic variations that modern philologists recognize as linguistically significant.\n\nThe legacy of these competing approaches continues to shape Anglo-Saxon studies. Contemporary scholars must navigate between uncritical presentism — reading modern values into medieval texts — and a naive empiricism that denies the inevitability of interpretive frameworks.

In the circumpolar regions of North America, indigenous communities have maintained complex food systems centered on the harvest of marine mammals, migratory caribou, and wild fish for millennia. These traditional food systems provide essential macronutrients and function as the organizational core of cultural identity and community cohesion. Advocates of food sovereignty have argued that the preservation of indigenous hunting rights is simultaneously a matter of public health and cultural survival.\n\nClimate change, however, has introduced a destabilizing variable. Accelerating Arctic warming has altered caribou migration patterns, reduced sea ice critical for marine mammal hunting, and introduced contaminants such as methylmercury into traditional food chains. These changes have forced communities into a double bind: continued reliance on traditional foods exposes residents to rising contaminant levels, while a shift toward imported market foods has been associated with elevated rates of diabetes and cardiovascular disease.\n\nSome public health researchers have proposed a hybrid approach combining traditional harvesting with contaminant monitoring. Critics contend that this reduces indigenous food systems to a set of nutritional inputs to be optimized, stripping them of their cultural and spiritual meaning.\n\nThe debate remains unresolved, but it has prompted a broader rethinking of what 'food sovereignty' means when the environmental conditions that sustained traditional food systems are themselves undergoing transformation.

During the Dutch Revolt against Habsburg Spain in the late sixteenth century, privateering — the state-sanctioned seizure of enemy merchant vessels — functioned not merely as a military tactic but as a critical engine of war finance. The rebel provinces, lacking the tax base of the Spanish crown, issued letters of marque to private ship captains who attacked Iberian and Portuguese trading vessels laden with spices, silver, and other high-value commodities. Prize courts in Dutch ports auctioned captured cargo, channeling a share of the proceeds to provincial war chests while enriching the privateers themselves. This arrangement proved self-reinforcing: captured vessels were refitted as warships or incorporated into an expanding merchant fleet, which in turn generated the customs revenue and commercial credit that sustained prolonged military operations. By the 1590s, privateering had become so profitable that it attracted investment from Amsterdam bankers who treated individual voyages as speculative ventures, effectively securitizing naval warfare. Historians increasingly recognize that this fusion of private profit and public military purpose laid the institutional groundwork for the Dutch East India Company, chartered in 1602.

The legal distinction between an employee and an independent contractor — a classification that determines eligibility for minimum wage protections, unemployment insurance, and employer-sponsored benefits — maps poorly onto the reality of platform-mediated work in the gig economy. Traditional employment law assigns contractor status to workers who control the manner, means, and timing of their work, while employees are those whose work is directed and supervised by the hiring entity. Gig workers, however, occupy an ambiguous middle ground: they choose when and whether to log onto a platform, a feature consistent with contractor status, yet the platform's algorithms exercise extensive control over pricing, task allocation, customer matching, and performance evaluation — functions traditionally associated with employer supervision. A ride-share driver, for instance, cannot negotiate fares, is penalized for declining too many ride requests, and can be permanently deactivated based on algorithmic assessment of customer ratings. This degree of algorithmic control approximates the supervisory authority that employment law treats as the hallmark of an employer-employee relationship, yet it is exercised through impersonal software rather than direct human management, creating a regulatory gap that existing legal categories were not designed to address.