short expository passage
The Green Sahara
Read the passage and choose one answer for questions 1–5.
TOEFL Reading · Formato actual
Esta tarea entrena lectura academica: idea principal, inferencia, proposito retorico y regreso al texto para justificar cada respuesta.
Respuesta directa: primero identifica la tesis del pasaje, luego separa evidencia textual de inferencias razonables. Si una opcion usa palabras del texto pero cambia la relacion logica, no es correcta.
Formato oficial: ETS lista Read an Academic Passage como una de las familias actuales de TOEFL Reading.
Estrategia WeLearn: practicamos pasajes cortos con preguntas explicadas antes de pasar a lecturas largas y control de tiempo.
Fuente oficial revisada: ETS TOEFL iBT Test Content and Structure.
Set 1 · Práctica interactiva
Práctica fija WeLearn. Reproduce familias de lectura y corrección local; no es adaptativa ni genera una puntuación oficial de ETS.
Después de las 5 preguntas del piloto verás una selección múltiple complementaria de WeLearn. Su resultado se informa por separado.
short expository passage
Read the passage and choose one answer for questions 1–5.
Respondidas: 0 de 6
Pasaje original
Wetlands are often described as natural buffers because they slow the movement of water between land and sea. During storms, marsh plants and shallow pools absorb part of the wave energy that would otherwise strike roads, farms, or neighborhoods directly. This protection is not absolute, but it can reduce damage when wetlands remain wide enough and healthy enough to function as a living barrier.
For many years, some coastal communities drained wetlands to create space for buildings or agriculture. The short-term benefit was clear: more usable land. Over time, however, those communities sometimes discovered that the removed wetlands had been providing a service that was expensive to replace. Artificial walls can protect a narrow area, but they may also redirect water pressure to nearby places.
Researchers now argue that coastal planning should combine engineered structures with restored wetlands. This mixed approach recognizes that natural systems and human-made defenses can support each other. A restored marsh may not stop every flood, but it can lower the force that reaches a wall, making the wall more effective and less costly to maintain.
Seed banks store seeds from many plant varieties in carefully controlled conditions. Their purpose is not simply to preserve rare plants as museum objects. By keeping genetic material available, seed banks give researchers and farmers a way to respond when disease, drought, or changing climate conditions threaten existing crops.
Genetic diversity matters because plants of the same crop can differ in useful traits. One variety of rice may tolerate flooding, while another may resist a particular insect. If agriculture depends on only a narrow set of varieties, a single disease can cause widespread damage. A broader genetic collection increases the chance that at least some plants will survive a new threat.
However, storing seeds is only part of the work. Seeds must be tested, replaced, and documented so that scientists know which traits they carry. Without accurate records, a seed bank may contain valuable material that cannot be used efficiently. For this reason, modern seed banks combine biological preservation with detailed information management.
Cities are often warmer than nearby rural areas because dark roofs, roads, and walls absorb sunlight during the day and release heat slowly after sunset. This pattern, known as the urban heat effect, can increase energy use when residents depend more heavily on air conditioning. It can also make outdoor spaces uncomfortable for pedestrians during periods of extreme heat.
One proposed response is to use reflective materials on roofs and pavements. These surfaces send more sunlight back into the atmosphere instead of storing it as heat. In several pilot projects, reflective roofs have lowered indoor temperatures and reduced cooling costs. However, the benefits depend on local design. A surface that reflects light into nearby windows, for example, may create glare or raise temperatures inside adjacent buildings.
For this reason, urban planners increasingly treat reflective materials as one tool rather than a complete solution. Trees, shade structures, ventilation corridors, and lighter surfaces can work together when they are placed according to how people actually move through the city. The strongest plans are not the ones that use a single technology everywhere, but the ones that match heat-reduction strategies to local streets, buildings, and daily routines.
Práctica guiada
Wetlands and coastal protection · Ítem 1 · Main idea
Wetlands and coastal protection · Ítem 2 · Inference
Wetlands and coastal protection · Ítem 3 · Rhetorical purpose
Seed banks and genetic diversity · Ítem 1 · Factual information
Seed banks and genetic diversity · Ítem 2 · Vocabulary in context
Seed banks and genetic diversity · Ítem 3 · Rhetorical purpose
Urban heat and reflective surfaces · Ítem 1 · Factual information
Urban heat and reflective surfaces · Ítem 2 · Rhetorical purpose
Urban heat and reflective surfaces · Ítem 3 · Inference
Respuestas explicadas
All three paragraphs build toward the idea that wetlands provide protection and work best when included in coastal planning.
Trampa: Option B is too absolute and contradicts the final paragraph. Option D invents disagreement that the passage does not mention.
The second paragraph says the short-term benefit was clear, but communities later discovered the wetlands had been providing an expensive-to-replace service.
Trampa: The passage does not say they could not build walls, and it does not present water quality as the reason for draining.
The wall example helps explain why a combined strategy can be stronger than relying on only one type of defense.
Trampa: TOEFL often uses extreme distractors. The passage supports mixed planning, not removing all walls.
The second paragraph says a broader genetic collection improves the chance that some plants survive disease or environmental threats.
Trampa: The passage supports careful documentation and controlled storage; it does not remove those needs.
Disease, drought, and climate conditions can endanger crops. That is the meaning of threaten in this context.
Trampa: Measure and organize may appear in scientific contexts, but they do not fit the risk relationship in the sentence.
The rice example illustrates the broader point that diversity inside one crop can provide different survival advantages.
Trampa: The passage does not compare flooding and insects by severity, and it does not limit seed banks to rice.
The first paragraph says dark roofs, roads, and walls absorb sunlight during the day and release heat slowly after sunset.
Trampa: The passage compares cities with rural areas, but it does not say rural areas transfer heat into cities.
The glare example qualifies the benefit of reflective materials and supports the idea that local design matters.
Trampa: The author does not reject reflective roofs; the final paragraph treats them as one useful tool among several.
The final paragraph says the strongest plans match several strategies to local streets, buildings, and daily routines.
Trampa: Option B is too absolute. The passage warns against using one technology everywhere.
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