Our original example, not a real test item
Why some cities are painting roofs white
Lecture transcript (you would only hear it)
"Today I want to look at a simple idea for cooling cities: painting roofs white. Dark roofs absorb most of the sunlight that hits them and release that heat into the air, which is one reason city centres are often several degrees warmer than the countryside around them. A white or reflective roof sends much of that sunlight back into the sky. Several cities have run trials, and buildings with reflective roofs needed noticeably less air conditioning on hot days. There are limits, though. In cold climates, a white roof can increase heating needs in winter, and the coating has to be cleaned or renewed every few years to stay reflective. So researchers see it as one useful tool, best combined with trees and green spaces, rather than a complete solution."
Notes
white roofs → cool cities
dark roof absorbs sun → heat → city warmer than country
white = reflect → trials: less A/C
limits: cold climate → more heating; clean/renew
concl: 1 tool + trees/green, not whole solution
Model retell (about 40 seconds)
"The lecture was about painting roofs white to cool cities. The speaker explained that dark roofs absorb sunlight and release the heat into the air, which helps make city centres warmer than the surrounding countryside, while white roofs reflect much of the sunlight away. Trials in several cities found that buildings with reflective roofs needed less air conditioning on hot days. However, there are drawbacks: in cold climates they can raise heating needs in winter, and the coating has to be maintained. The speaker concluded that white roofs are a useful tool, best combined with trees and green spaces, but not a complete solution."
Why it works
- It opens with the topic, then gives the cause, the evidence, the limits and the conclusion, in the lecture's order.
- It paraphrases rather than repeating long stretches of the lecture word for word.
- Its links (which, while, however, concluded that) show how the ideas relate, which the higher Content levels describe.