Narrator: Listen to part of a lecture in an environmental science class. Professor: Okay, so we've been talking about renewable energy sources, and today I want to focus on tidal power. Unlike solar or wind, tidal energy is predictable because it's driven by the gravitational pull of the moon and the sun. However, its implementation faces significant challenges. One major issue is the high initial cost of building tidal barrages or underwater turbines. Another is the environmental impact on marine ecosystems. For example, turbines can injure fish, and barrages can disrupt the natural flow of sediment and nutrients. Yet, there's a growing interest in smaller, less invasive designs, like tidal lagoons, which are partially enclosed. These might reduce ecological damage while still generating electricity. But even with these advances, the question remains whether tidal power can become cost-competitive with other renewables. What do you think? Any initial reactions?
❓ Pregunta What is the professor's main point about tidal power?
A. A) Tidal power is more reliable than solar and wind but has high costs and environmental drawbacks.
B. B) Tidal power is the most cost-effective renewable energy source available today.
C. C) Tidal power has no significant environmental impact compared to other renewables.
D. D) Tidal power is too unpredictable to be a viable energy source.
✅ Respuesta correcta
A) Tidal power is more reliable than solar and wind but has high costs and environmental drawbacks.
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