ST_021
听力音频：
综合写作
Since the common carp was introduced to Australian waters about two centuries ago, it has become an invasive species in many Australian waterways, where it competes with native fish and harms local ecosystems. Scientists are currently investigating several methods for reducing carp numbers in order to improve ecosystems in Australia.
First, it is possible to reduce carp populations through commercial fishing. In the United States, for instance, the Asian carp has been a harmful invasive species for many years, but its numbers have been reduced in several areas by increased commercial fishing. This occurred because government programs encouraged commercial fisheries to catch and sell more carp and because carp was promoted as a fish that is especially good to eat. Commercial carp fishing could similarly be encouraged in Australia to reduce carp populations.
Another option is to poison the carp. Bait food injected with a powerful toxin can be thrown into lakes and ponds; carp that eat these baits will die. To keep native fish species from being killed by these poisoned baits, they can be made attractive only to carp. Unlike many fish, carp can eat plants and are attracted to certain kinds of plant material, like corn. So, if the poisoned baits are made of corn or resemble corn, they will only get eaten by the carp, and only the carp will get killed by the poison.
A final option involves genetic engineering. In the laboratory, scientists have found a way to modify or change individual carps’ genes so that they only produce male offspring without producing any females. Scientists hope to introduce such genetically modified carp into the infested waterways, where they will breed with the carp that are already present. As these modified carp spread their genes throughout the carp population, carp offspring will increasingly be male, reducing the number of carp eggs that get produced.
Question:Summarize the points made in the lecture, being sure to explain how they respond to the specific concerns expressed in the reading passage.
学术写作：
教授：民宿和酒店的竞争越来越大，这是否是个好趋势？
Kelly：是好的。支持当地经济，旅游者也节约钱。
Paul：不好。酒店更容易交朋友。
Dr. Achebe: In recent years, there has been a noticeable shift in the choices travelers make for their accommodations. Many are now opting for privately owned residences over traditional hotels. This change is reshaping the travel industry and creating a competitive landscape between these two types of lodging. Do you think the increased competition between privately owned residences and traditional hotels is a positive trend? Why or why not?
Kelly: Yes, it benefits homeowners by providing them with an additional income stream. For travelers, it often means more affordable accommodation options. For instance, during my last vacation, l chose a privately owned residence and saved a significant amount compared to hotel prices. This trend enhances travel experiences while supporting local economies.
Paul: No, l don’t think it’s a positive trend. Staying in hotels offers more opportunities to meet new people and socialize. l stayed at a hotel last year and met other travelers during breakfast and in common areas. This aspect of hotel stays can enhance the travel experience by fostering new connections.
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