Listen to part of a lecture in an environmental science class.
Professor: Today we’re going to talk about urban heat islands, a phenomenon where cities are significantly warmer than surrounding rural areas. One major cause is the replacement of natural surfaces with asphalt and concrete, which absorb and retain heat. Another factor is the lack of vegetation, since trees and plants provide shade and release moisture through transpiration, cooling the air. Additionally, waste heat from vehicles, air conditioners, and industrial processes adds to the effect.
Now, some solutions exist. For example, cities can implement green roofs—planting vegetation on building tops—which not only insulate buildings but also reduce runoff. Another approach is using cool pavements that reflect more sunlight. However, these solutions require initial investment and maintenance. But the benefits include lower energy costs, improved air quality, and reduced heat-related illnesses. So, while the problem is complex, we have effective tools to mitigate it.
❓ Pregunta What does the professor mainly discuss?
A. A. The causes and solutions of urban heat islands
B. B. The history of city planning in industrialized nations
C. C. The role of transpiration in global cooling
D. D. The economic costs of green infrastructure
✅ Respuesta correcta
A. The causes and solutions of urban heat islands
TOEFL Listening Tips
Skim the questions first to predict the content
Watch for signal words in lectures and conversations (however, actually, in fact)
For main idea questions, focus on the beginning; for detail questions, focus on examples and data
For attitude questions, pay attention to the speaker's tone and word choice
Take notes on keywords; don't try to write down every word