Narrator: Listen to part of a lecture in an environmental science class. Professor: Today we're going to talk about the concept of urban heat islands. Essentially, cities are often warmer than surrounding rural areas because of human activities and the concentration of heat-absorbing materials like concrete and asphalt. These surfaces absorb solar radiation during the day and release it slowly at night, causing temperatures to remain elevated. Vegetation, on the other hand, provides shade and releases moisture through evapotranspiration, which cools the air. So, cities with limited green spaces tend to have more intense heat islands. One solution is to increase the number of parks and green roofs. Another is to use reflective materials on buildings and roads to reduce heat absorption. However, these solutions require significant investment and planning. Interestingly, a simple change like planting more trees along streets can lower local temperatures by several degrees, but the effect is not uniform across the city. It's a complex issue that involves urban design, climate, and social factors.
❓ 質問 According to the professor, what is a major cause of the urban heat island effect?
A. A. The high concentration of heat-absorbing materials in cities
B. B. The lack of wind circulation in urban areas
C. C. The release of greenhouse gases from vehicles
D. D. The reduction of solar radiation due to pollution
✅ 正解
A. The high concentration of heat-absorbing materials in cities
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