Narrator: Listen to part of a lecture in an environmental science class. Professor: Today we're talking about urban heat islands—areas in cities that 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 provide shade and release moisture through transpiration. However, there are mitigation strategies. For instance, painting rooftops white or using reflective materials can reduce heat absorption. Also, creating green roofs—covering rooftops with plants—helps insulate buildings and lower ambient temperatures. But here's a surprising point: some studies suggest that simply planting more trees in streets might not be as effective as we think, because in narrow streets, trees can block wind and trap heat. So, urban planners must consider local geometry and climate when designing solutions. The key is a combination of approaches tailored to each city's specific layout.
❓ คำถาม What does the professor imply about planting trees in narrow streets?
A. A. It is the most effective way to reduce urban heat islands.
B. B. It can sometimes increase heat by blocking airflow.
C. C. It has no effect on the surrounding temperature.
D. D. It is only useful when combined with white rooftops.
✅ คำตอบที่ถูกต้อง
B. It can sometimes increase heat by blocking airflow.
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