本文是tpo44听力答案及解析Lecture4，通过对
Lecture 4
1. What is the main purpose of the talk? 【目的主旨题】
A. To explain the mechanical functioning of barrages.
B. To discuss some possible ecological effects of building barrages.
C. To discuss the effects of ocean tides on coastal ecosystems.
D. To describe ways to increase biological productivity of estuaries.
答案：B
破题关键词汇：
解析： (从29秒开始，原文重现：There is currently a lot of interest in harnessing the power of the oceans, of the ocean tides…One place where this tidal energy can be harnessed is at a shallow body of water, such as an estuary…And one way to harness that energy is by building a structure called a barrage there…)
教授开篇提出如今对海洋能源来产新能源，费用不高还节能环保，接着提出在入海口修建大坝能实现。选项A解释大坝的功能不是此篇主要目的;选项B讨论一些可能修建大坝的生态效应，与原文用意一致;选项C讨论海浪对海岸生态系统的影响，不是主要目的;选项D为了描述增加入海口生物生产力的方法，与原文不符。
2. What is the professor's opinion when the man expresses concern about marine life on the mud flats? 【态度题】
A. She thinks the environmental impact of barrages would be worse for birds than for fish.
B. She agrees that any damage to the mud flats would probably be irreversible.
C. She feels that the situation is more complex than the man realizes.
D. She does not believe that the mud flats support a wide variety of animal species.
答案：C
破题关键词汇：marine life, mud flats
解析： (从2:29秒开始，原文重现：Student: But don't lots of birds rely on exposed mudflats for food? I mean, don't they eat tiny animals that live in the mud? And what about those tiny animals? What would happen to them if the mudflats were endangered?
Professor: So you are seeing some of the potential problems with the barrage. But consider this, right now, the water in an estuary is very cloudy. The tidal currents are constantly churning up the sediments that rivers deposit in the estuary. But a barrage would reduce the tidal currents. So a lot of that sediment would settle to the floor of the estuary.)
原文中学生提出如果泥摊受影响的话，海洋生物将会随之受牵连。接着教授说这只是大坝潜在的问题，但大坝也会减少潮汐。选项A教授认为大坝的环境影响，比起鱼来说鸟的更为严重。原文并没有对鱼和鸟的环境进行比较;选项B她同意任何对泥滩的破坏都将可能是不可避免的，不是教授的想法;选项C她认为比起男生的担忧处境更复杂，与原文意思相符;选项D她认为泥滩不会有不同的动物物种，与原文不符。
3. The professor mentions a change in the quantity of fish caught near a barrage in France. What most likely happened to the water in the estuary as a result of the construction of the barrage? 【推断题】
A. The water has become clearer.
B. The water has become saltier.
C. The water has become polluted
D. The water level has risen.
答案：A
破题关键词汇：fish, France
解析： (从3:22秒开始，原文重现： Yes, there are several in operation. There is one in France. Now, they have to be careful there about how they turn on the turbines because they create currents and waves that can affect boats. But I haven't read about any major ecological problems. In fact, the fishing is supposed to have improved. Plus there is even more bird life.)
原文中教授提到法国的一个大坝如今对如何发动涡轮非常小心，因为它产生的潮汐会影响船，对生态的影响尤其是鱼和鸟都十分有利。这些与前面教授的观点相呼应。选项A水变的更干净，通过原文中的鱼的生态环境改进了可以推断出水质变好了;选项B水变的更咸了，与原文推断不符;选项C水受的污染更严重了，也与原文推断不符;选项C水平面升高了，在原文中并未被提及。
4. What does the professor say is a criticism of the proposed barrage at the Severn River in Great Britain? 【细节题】
A. It would damage nearby buildings.
B. It would attract harmful species to the region.
C. It would not be as large as the barrage in France.
D. it would be too expensive to build.
答案：D
破题关键词汇：Severn River，Great Britain
解析： (从3:44秒开始，原文重现：There has been one proposed for the estuary of Great Britain's Severn River, one of the largest estuaries in the world…Critics say that it would better to use that money for something else, such as improving the energy efficiency of buildings. You could make a lot of buildings more efficient with all that money and that would reduce the need for electricity.)
原文中提到将在Severn River全球最大的入海口建大坝，除了环境因素的考虑，这个工程将会斥巨资建造，很多人批判说那些钱应该用在如高效节能上。选项A中将破坏周围的建筑，与原文不符;选项B将会吸引有害的物种，与原文不符;选项C不会和法国的大坝一样大，不是原文中所批判的内容;选项D建造的花费太贵，与原文信息相符。
5. Why does the professor say this: 【重听题】
A. To request that the student answer in greater detail.
B. To introduce a new topic for discussion.
C. To make the student's statement more accurate.
D. To repeat a point that she had not stated clearly.
答案：B
破题关键词汇：
解析： (从57秒开始，原文重现： Student：An estuary is where a river enters the ocean. The fresh water meets the ocean water. Sometimes it is covered in water. Sometimes it is not.
Professor：Some parts of the estuary, as the tides go in and out, but other parts are always submerged.)
原文中学生讲到入海口是河流汇入海洋，淡水汇入海水的地方。有时被水覆盖有时则没有。教授接着说入海口的一些部分，由于潮汐涨退，但有些部分总是被淹没的。选项A要求学生的答案在更详细些，与原文不符;选项B为了介绍一个新的话题去讨论，与原文意思相符;选项C为了让学生的阐述更准确，与原文无关;选项D为了重复一个她没有陈述清楚的观点，与原文无关。
本文的内容是托福tpo44听力答案及解析Lecture4，希望对你们备考提供更多指导!