综合写作：
The Eocene epoch began 55 million years ago with a rapid increase in global temperatures, the Eocene warming. The warm period lasted for 20,000 years. It was so warm during this period that ocean water at the poles supported tropical life-forms. Climatologists have proposed several theories to explain the Eocene warming.
Some scientists have hypothesized that changes in the ocean currents caused the warming. It is well documented that at the start of the Eocene many ocean currents drastically changed direction, perhaps because of a change in the position of the continents. Deep-water currents in the Atlantic Ocean, flowing in new directions, transported warm water from the tropics toward the poles. Proponents of the ocean current theory point to this change as the cause of the Eocene warming.
The reading suggests that the warming might be caused by the changed direction of ocean currents. However, the listening objected this theory. According to the professor, computer simulation showed that even if this change of ocean current could have brought some heat, it is not adequate to explain the Ecocene Warming.
A second theory proposes that an enormous comet struck Earth and initiated the Eocene warming. When comets strike Earth, they can create atmospheric conditions that lead to the increase in atmospheric temperatures. The comet theory supported by the discovery of a high concentration of magnetic particles in a thick layer of clay that dates to the beginning of the Eocene. Since comet collisions often deposit magnetic particles in the soil, the clay layer provides good evidence for the comet theory.
A third theory attributes the warming to the release of methane from oceans into the atmosphere. Substantial quantities of methane are usually trapped on the floor of the ocean. However, there is evidence that at the beginning of Eocene, changes in the oceanic environment caused large portions of the methane to escape Methane is a potent greenhouse gas, and once it escape into the atmosphere, it can cause a rise of atmospheric temperatures and therefore, events such as the Eocene warming.
听力音频
学术写作：
Dr. Gupta
We have read studies that explain the negative impact of social media on both children and adults. Many believe that social media will remain widely used in the future, since it is both popular and useful in some contexts, but because of the problems it poses, it should be regulated in some way. In your opinion, should governments regulate social media platforms, or should social media companies regulate their platforms themselves? Why do you think so?
Andrew
I believe social media companies should regulate themselves. There are plenty of social media platforms on the market, so the competition is tough. For example, to appeal to parents, a social media platform could publicize that they have stringent regulations for children’s use of the platform, and in this way it could attract more users who care about children’s safety.
Claire
Social media companies should be taking an active role in combatting the negative effects, but that is not really happening. I hear many stories of false information spreading around, sometimes causing irreparable damage to people’s reputations. Therefore, the government should put stricter regulations on the companies, and they should be punished for not following the rules.
