Listen to part of a lecture in an environmental science class. Professor: Today we're discussing the concept of 'urban heat islands.' As you know, cities tend to be warmer than surrounding rural areas. This is mainly because concrete and asphalt absorb and re-emit solar heat more than vegetation does. Also, waste heat from vehicles and buildings adds to the effect. A common solution is planting more trees, which provide shade and release moisture through transpiration. However, recent research suggests that reflective surfaces, like cool roofs, may be more effective in certain climates. A study in Los Angeles found that cool roofs could lower city-wide temperatures by about two degrees Fahrenheit, while trees had a smaller effect due to water limitations. But trees offer additional benefits, such as absorbing carbon dioxide and improving mental health. So the choice depends on local conditions and priorities. What's the main point the professor makes about solutions?
❓ 質問 What is the professor's main point about solutions to urban heat islands?
A. Trees are always the best solution because of their multiple benefits.
B. Cool roofs are effective but only in dry climates like Los Angeles.
C. The best solution varies depending on local conditions and goals.
D. Reflective surfaces are more effective than trees in all cases.
✅ 正解
The best solution varies depending on local conditions and goals.
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