Listen to part of a lecture in an environmental science class.
Professor: Today we're going to talk about a surprisingly effective tool in combating climate change: beavers. Yes, the dam-building rodents. Recent studies show that beaver dams create wetlands that store significant amounts of carbon. When beavers build dams, they flood surrounding areas, creating ponds and marshes. The waterlogged conditions slow down the decomposition of organic matter, like leaves and wood, which means carbon gets locked in the sediment instead of being released into the atmosphere. Furthermore, these wetlands act as natural filters, improving water quality. They also provide critical habitat for many species, from fish to birds. Some researchers even call beavers 'ecosystem engineers' because of their profound impact. However, there's a catch. Beavers can cause flooding in agricultural areas, leading to conflicts with farmers. So, conservation groups are working on non-lethal solutions, like installing 'beaver deceivers'—pipes that control water levels without removing the dams. The goal is to balance ecological benefits with human needs.
❓ คำถาม What is the main point the professor makes about beavers?
A. They are a major cause of flooding in agricultural areas.
B. They are a valuable natural ally in reducing atmospheric carbon.
C. Their dams are being removed to protect farmland.
D. They are the primary engineers of most wetland ecosystems.
✅ คำตอบที่ถูกต้อง
They are a valuable natural ally in reducing atmospheric carbon.
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
