Listen to part of a lecture in an environmental science class. The professor is discussing the concept of urban heat islands.
"Today we're going to talk about urban heat islands, which are areas in cities that are significantly warmer than their surrounding rural areas. This phenomenon occurs because materials like concrete and asphalt absorb and re-emit more solar energy than natural landscapes such as trees and grass. Additionally, human activities, including transportation and industrial processes, generate excess heat. The temperature difference can be as much as 10 degrees Fahrenheit on clear, calm nights.
One interesting aspect is the role of vegetation. Trees provide shade and release moisture through a process called transpiration, which cools the air. So, cities with more green spaces tend to have less severe heat island effects. Urban planners are now using this knowledge to design cooler cities. For example, they might plant more trees on streets, create green roofs, or use reflective materials for pavements. These strategies not only reduce temperatures but also lower energy consumption for air conditioning and improve air quality."
❓ 문제 What is the main topic of the lecture?
A. A. The process of transpiration in trees
B. B. The causes and mitigation of urban heat islands
C. C. The design of energy-efficient buildings
D. D. The effects of climate change on rural areas
✅ 정답
B. The causes and mitigation of urban heat islands
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