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. This happens mainly because of the abundance of concrete and asphalt, which absorb and re-emit heat from the sun more than natural landscapes do. Additionally, waste heat from vehicles and buildings adds to the effect. But there are mitigation strategies. For example, planting trees and creating green roofs can provide shade and cool the air through evapotranspiration. Another approach is using cool pavements that reflect more sunlight and absorb less heat. However, these solutions aren't always equally effective. Cool pavements work best in hot, sunny climates, while green roofs are more beneficial in temperate regions. Interestingly, a study in Los Angeles found that increasing urban vegetation by 10% could lower surface temperatures by up to 4 degrees Celsius, but it would also increase humidity, which might make people feel less comfortable. So, it's a complex trade-off that city planners must consider.
❓ 문제 What does the professor say about cool pavements?
A. A. They are most effective in temperate climates.
B. B. They are less effective than green roofs in all regions.
C. C. They work particularly well in hot, sunny areas.
D. D. They increase humidity and reduce comfort.
✅ 정답
C. They work particularly well in hot, sunny areas.
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