First, take three minutes to read this article:

In recent years, the use of volcanic rock in the construction of homes has gained attention due to its numerous advantages. This natural material, formed from volcanic lava, offers significant benefits that make it an excellent choice for building. 

First, volcanic rock is renowned for its exceptional durability. Unlike conventional building materials such as concrete and wood, volcanic rock is highly resistant to weathering, erosion, and natural decay. Its robust nature means that structures built with volcanic rock can withstand harsh environmental conditions, including extreme temperatures, heavy rainfall, and high winds, without deteriorating over time. This durability reduces the need for frequent repairs and replacements, making volcanic rock a cost-effective option in the long run.

In addition, the porous nature of volcanic rock enables it to trap air within its structure, providing an excellent source of natural insulation. This helps to maintain a stable indoor temperature, keeping homes warm in the winter and cool in the summer. As a result, homes constructed with volcanic rock require less energy for heating and cooling, leading to lower utility bills and a reduced carbon footprint. This energy efficiency is particularly advantageous in regions with extreme climate conditions.

Finally, using volcanic rock in construction has notable environmental benefits. The extraction and processing of volcanic rock is more environmentally-friendly than the production of other building materials. Moreover, volcanic rock is abundant and often found locally, reducing the need for long-distance transportation and associated carbon emissions. Its use can contribute to more sustainable construction practices and support the growing demand for eco-friendly building solutions.

Next, listen to the following lecture:


You have twenty minutes to answer the following question.  You can see to the article as you write your essay.  You may not listen to the lecture again.

Summarize the points made in the lecture, being sure to explain how they oppose specific points made in the reading passage.

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Sample Response

Here is a sample essay:

The reading and the lecture are both about using volcanic rock to construct homes.  While the reading describes three advantages of this building technique, the lecturer challenges each of the proposed benefits.  He does not believe that volcanic rock is a really useful building material.

First, the author notes that volcanic rock is durable and resistant to natural processes like weather and erosion.  According to the article, this reduces the need for costly repairs and makes it a very cost-effective choice in the long run.  The professor, though, challenges this idea.  He claims that volcanic rock is extremely brittle, which could be problematic during disasters like earthquakes.  In fact, he notes that buildings made with volcanic rock could need costly repairs after such events.  In contrast, modern materials like concrete are designed to withstand situations like this.

Next, the author argues that volcanic rock is an excellent natural insulator.  This makes it a cost-effective option, particularly in regions with extreme climates.  In contrast, the professor notes that this is an exaggeration.  He mentions that interior temperatures fluctuate in buildings where it is used and that temperatures are more stable in buildings that use advanced options like foam and fiberglass which are designed for this purpose.

Finally, the author points out that volcanic rock is an environmentally-friendly option because it is easier to extract than other materials.  It can also be found locally, which reduces the need for long-distance transportation.  On the other hand, the professor says that the extraction of volcanic rock can still have negative impacts on natural environments and landscapes.  Moreover, he says that it involves the use of heavy machinery and fossil fuels, which are not environmentally-friendly.