Narrator: Listen to part of a lecture in an environmental science class. Professor: Today we're discussing urban heat islands, a phenomenon where cities are significantly warmer than surrounding rural areas. One major cause is the replacement of natural surfaces with materials like concrete and asphalt, which absorb and re-radiate solar energy. Another factor is the lack of vegetation, since trees and plants provide shade and release moisture through transpiration, cooling the air. Interestingly, the heat island effect isn't uniform across a city. Dense downtown areas with tall buildings can trap heat, while parks and green spaces create cooler pockets. To mitigate this, some cities have adopted 'green roofs'—covering rooftops with vegetation—which can lower building temperatures and reduce energy use. However, the initial cost is high, and maintenance requires specialized knowledge. Still, the long-term benefits, including improved air quality and reduced stormwater runoff, often outweigh the drawbacks. Now, let's consider a case study from Chicago…
❓ Вопрос According to the professor, what is one reason why urban heat islands are not uniform across a city?
A. A) Because some cities have more vehicles than others
B. B) Because dense downtown areas with tall buildings can trap heat, while parks create cooler pockets
C. C) Because rural areas are always cooler due to farming activities
D. D) Because green roofs are only used in certain neighborhoods
✅ Правильный ответ
B) Because dense downtown areas with tall buildings can trap heat, while parks create cooler pockets
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