Narrator: 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. The main cause is the replacement of natural surfaces with materials like asphalt and concrete, which absorb and retain heat. Additionally, waste heat from vehicles and air conditioners adds to the effect. But there are solutions. One effective strategy is increasing vegetation, such as planting trees and creating green roofs. Plants provide shade and release moisture through transpiration, which cools the air. Another approach is using cool roofs, which are painted with reflective coatings to bounce sunlight back into the atmosphere. Studies show that cool roofs can lower a building's temperature by several degrees, reducing energy consumption for air conditioning. However, the choice of solution often depends on local climate and urban design. For example, in dry regions, planting trees might require too much water. So, city planners must weigh the costs and benefits. Any questions?
❓ คำถาม What does the professor say about cool roofs?
A. They are more effective than planting trees in all climates.
B. They work by reflecting sunlight away from buildings.
C. They require significant water to maintain.
D. They absorb heat and release it slowly at night.
✅ คำตอบที่ถูกต้อง
They work by reflecting sunlight away from buildings.
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