Engineering For Sustainable Development - IELTS Listening Answers & Explanations
From IELTS Practice Test Plus 3 Academic Listening Test 7 · Part 4 · Questions 31–40
Audio
Questions
Questions 31–40 Note Completion
Complete the notes below.
Write ONE WORD ONLY for each answer.
Engineering for sustainable development
The Greenhouse Project (Himalayan mountain region)
Problem
- Short growing season because of high altitude and low 31
- Fresh vegetables imported by lorry or by 32, so are expensive
- Need to use sunlight to prevent local plants from 33
- Previous programmes to provide greenhouses were 34
New greenhouse
Meets criteria for sustainability
- Simple and 35 to build
- Made mainly from local materials (mud or stone for the walls, wood and 36 for the roof)
- Building and maintenance done by local craftsmen
- Runs solely on 37 energy
- Only families who have a suitable 38 can own one
Design
- Long side faces south
- Strong polythene cover
- Inner 39 are painted black or white
Social benefits
- Owners' status is improved
- Rural 40 have greater opportunities
- More children are educated
Answers & Explanations Summary
| # | Answer | Evidence | Explanation |
|---|---|---|---|
| Q31 | rainfall | In the Himalayan mountains, fresh vegetables and other crops can only be grown outside for about 90 days during the summer, because the altitude of the region is around 3,500 meters and because the rainfall is so low | Excerpt/Transcript Explanation: The transcript states that plants can only grow for 90 days in the summer because the land is high and there is very little rain. Answer Explanation: The answer 'rainfall' means the amount of rain that falls in an area. Reason For Correctness: The correct answer is 'rainfall' because the lecturer lists two reasons why the growing season is short: the high altitude and the lack of rain. In the transcript, the phrase 'the rainfall is so low' specifically explains why plants cannot grow for long periods, matching the phrase 'low rainfall' in the notes. |
| Q32 | air / plane | They arrive by truck in summer or by air in winter, which makes them expensive | Excerpt/Transcript Explanation: The transcript explains that fresh vegetables are brought to the area using trucks or by air (airplanes). Because they have to travel this way, the vegetables cost a lot of money. Answer Explanation: The answer "air/plane" refers to the method used to transport fresh vegetables into the Himalayan mountain regions when it is too cold to grow them locally. Reason For Correctness: The correct answer is "air" because the lecturer explains that because it is very cold in the winter, fresh food cannot grow. Therefore, it must be brought in from other places (imported) using trucks in the summer or by air in the winter. In the notes, the word "lorry" is used as a synonym for "truck," and the missing word describes the second method of travel, which is "air." |
| Q33 | freezing | So, an engineering solution was needed to exploit the sun’s energy and protect locally produced plants from freezing during winter | Excerpt/Transcript Explanation: The transcript says they needed a smart building plan to use the sun's light to stop local plants from turning to ice during the winter. Answer Explanation: The answer "freezing" describes what happens to plants when it is so cold that the water inside them turns to ice. Reason For Correctness: The correct answer is "freezing" because the lecturer explains that engineers needed to find a way to use the sun's power (sunlight) to keep local plants safe during the cold winter. The transcript uses the word "protect," which means the same as "prevent" in the notes, to show they wanted to stop the plants from getting too cold. |
| Q34 | unsuccessful | And in fact, there had been programs in the past to provide greenhouses, but these were unsuccessful | Excerpt/Transcript Explanation: The transcript states clearly that older plans to give greenhouses to the area were not successful. Answer Explanation: The answer "unsuccessful" means that older projects to build greenhouses did not work well or failed. Reason For Correctness: The correct answer is "unsuccessful" because the speaker mentions that there were projects in the past to give greenhouses to people in the mountains. However, those projects failed. The speaker uses the word "unsuccessful" to say they did not work out because the greenhouses were not made correctly for that specific place. |
| Q35 | cheap / inexpensive | Well, first of all, the new greenhouse is designed to be relatively simple, so construction is cheap | Excerpt/Transcript Explanation: The transcript says that because the greenhouse design is not complicated, it costs very little money to put it together. Answer Explanation: The answer means that building the greenhouse does not cost a lot of money. Reason For Correctness: The correct answer is "cheap" (or "inexpensive") because the lecturer explains that the greenhouse has a basic design. Because it is basic or "simple," the cost to build it ("construction") is low. Keywords to note are "simple," which refers to the design, and "construction," which refers to the building process. |
| Q36 | grass | The main roof is generally made from locally available poplar wood, with water-resistant local grass for the covering | Excerpt/Transcript Explanation: The transcript states that the top part of the greenhouse (the roof) is built using local wood and a specific kind of local grass that keeps the rain out. Answer Explanation: The answer is grass, which is a type of green plant that grows on the ground and is used here to cover the top of the building. Reason For Correctness: The correct answer is 'grass' because the lecturer describes the materials used for the roof. He mentions that the main part of the roof is made of local wood (poplar wood) and the outer covering is made of water-resistant local grass. Since the question asks for a material used for the roof alongside wood, 'grass' is the specific material mentioned in the text. |
| Q37 | solar | Then, the greenhouse is designed to run on solar power alone | Excerpt/Transcript Explanation: The transcript explains that the building is made to operate using only power from the sun, without needing any other type of heating. Answer Explanation: The answer means using the light or heat from the sun to make something work. Reason For Correctness: The correct answer is "solar" because the lecturer states that the greenhouse is made to work using only "solar power." In the notes, the word "solely" means the same thing as "alone" or "only," and "energy" is a synonym for "power." |
| Q38 | site / location / place | They have to have a site which is suitable for constructing it on | Excerpt/Transcript Explanation: The transcript explains that families must have a specific piece of land (a site) that is good for building before they are allowed to own a greenhouse. Answer Explanation: The answer identifies the specific piece of land or area required for building the greenhouse. Reason For Correctness: The correct answer is based on the list of requirements for families who want to own a greenhouse. The lecturer explains that for a family to be chosen, they must possess a 'site'—which is a synonym for a location or place—that is appropriate for building the greenhouse structure. |
| Q39 | walls | On the inside of the greenhouse, the walls are painted. The rear and west-facing walls are black to improve heat absorption, but the east-facing wall is white to reflect the morning sunlight onto the crops inside | Excerpt/Transcript Explanation: The transcript explains that the surfaces inside the greenhouse are painted. Some are black to catch heat, and others are white to reflect light. Answer Explanation: The answer is walls, which are the vertical structures that enclose or divide the space inside a building. Reason For Correctness: The correct answer is 'walls' because the lecturer explains that the internal surfaces of the greenhouse are painted differently. Specifically, some are painted black to soak up heat, and one is painted white to bounce light onto the plants. These different colors help the greenhouse work better. |
| Q40 | women | Secondly, because in rural areas it is women who usually grow the food, the greenhouses have increased their opportunities | Excerpt/Transcript Explanation: The transcript explains that since women are the ones who normally farm in these villages, the new greenhouses give these women a better chance to improve their nutrition and make more money. Answer Explanation: The answer refers to the specific group of people living in the countryside who are given more chances to succeed because of the greenhouses. Reason For Correctness: The correct answer is women because the lecturer mentions that in rural areas, it is typically the women who grow the food. Because of this, the new greenhouses have directly increased their opportunities to improve their lives and their family's income. Pay attention to terms like 'rural areas' (which means the countryside) and 'increased their opportunities' (which means giving someone a better chance or more ways to succeed). |
Transcript
Narrator: Test 7, Section 4. You will hear a lecturer talking to a group of engineering students about the design of a greenhouse. Before you listen, you have some time to look at questions 31 to 40. Now listen and answer questions 31 to 40.
Lecturer: Good afternoon. This is the first of a series of lectures I’ll be giving about engineering for sustainable development. I’ll be presenting examples of engineering projects from a variety of contexts, and today I’m going to talk about a project to design a new kind of greenhouse for use in the Himalayan mountain regions.
First of all, I’ll tell you about the problem which was the context for this project. In the Himalayan mountains, fresh vegetables and other crops can only be grown outside for about 90 days during the summer, because the altitude of the region is around 3,500 meters and because the rainfall is so low. In winter, temperatures fall below -25°C, so fresh vegetables have to be imported. They arrive by truck in summer or by air in winter, which makes them expensive. Local people rely on dried leafy vegetables and stored root crops during the winter and rarely eat fresh vegetables.
But despite the sub-zero temperatures, the skies over the region are cloudless, and there are over 300 sunny days per year. So, an engineering solution was needed to exploit the sun’s energy and protect locally produced plants from freezing during winter. And in fact, there had been programs in the past to provide greenhouses, but these were unsuccessful. The greenhouses weren’t adapted for local conditions, so they tended to fall into disuse. So, a few years ago, a project was initiated to design a better greenhouse, one which would meet the criteria for sustainability.
So, what are the criteria for sustainability? Well, first of all, the new greenhouse is designed to be relatively simple, so construction is cheap. Locally available materials are used wherever possible. The walls are generally constructed of mud bricks made locally, although in areas of high snowfall, more resilient walls of stone are needed. Rammed earth is also used.
The main roof is generally made from locally available poplar wood, with water-resistant local grass for the covering. In addition, the construction and maintenance of the greenhouse is done by local craftsmen. So local stonemasons are employed to build the greenhouse walls, and specialized training is provided for them wherever necessary.
Then, the greenhouse is designed to run on solar power alone. There’s no supplementary heating. And lastly, families are selected to own one of the new greenhouses with great care. They have to have a site which is suitable for constructing it on. They also have to be keen to make a success of using it, and also to share the produce with the wider community through sale or barter. Potential owners are taken to see existing greenhouses before they make a final decision about having one.
So, those are the features which make the project sustainable. And now, I’ll briefly describe the design of the greenhouse. The greenhouses are oriented very carefully along an east-west axis, so that there’s a long south-facing side. The transparent cover on the south-facing side is made from a heavy-duty polythene, which should last for at least five years.
On the inside of the greenhouse, the walls are painted. The rear and west-facing walls are black to improve heat absorption, but the east-facing wall is white to reflect the morning sunlight onto the crops inside. Finally, there’s a door in the wall at one end, and vents are incorporated into the roof, the door, and the wall at the other end, to enable control of humidity and prevent overheating.
I’ll turn now to the benefits which have resulted from the introduction of these new greenhouses. These benefits are of various kinds, but for now, I’ll just mention the social benefits. First of all, people who own a greenhouse gain social standing in their communities because they provide vegetables for the wider community for regular consumption as well as for festivals, and they also earn income.
Secondly, because in rural areas it is women who usually grow the food, the greenhouses have increased their opportunities. They bring the benefits of improved nutrition and increased family income from the sale of surplus produce. And thirdly, as a result of their improved financial position, some families can now afford to educate their children for the first time.
Narrator: That is the end of section 4. You now have half a minute to check your answers. That is the end of the listening test. You now have 10 minutes to transfer your answers to the separate answer sheet.