托福聽力lecture并列型分析

對于部分的文章分析，之前我們已經(jīng)做過很多期了，大家的反響都不錯，今天我們繼續(xù)就lecture的并列型結(jié)構(gòu)給大家分析一篇文章，希望能夠給大家?guī)�來幫助�?/p>

之前我們介紹了lecture的并列型結(jié)構(gòu)，一般是圍繞某一個主題并列平行展開去講解。這類結(jié)構(gòu)沒有之前我們見到的直線型結(jié)構(gòu)那么好區(qū)分，因?yàn)樗麤]有明顯的表示時間地點(diǎn)人物的信號詞，但是這種結(jié)構(gòu)類型是我們TPO和考試中出現(xiàn)的比較多的結(jié)構(gòu)類型。我們這次分析一篇按并列結(jié)構(gòu)分層的一篇文章。

今天我們以TPO31-L2為例，給大家講解一下。

As we’ve discussed, Earth’s crust is made up of large plates that rest on a mantle of molten rock. These plates…uh…now these tectonic plates support the continents and oceans. Over time, the tectonic plates move and shift, which moves the continents and the ocean floors too. Once it was understood how these plates move, it was possible to determine past movements of Earth’s continents and how these slow movements have reshaped Earth’s features at different times. 開篇引出了今天的主題，我們可以通過學(xué)習(xí)板塊運(yùn)動去預(yù)測板塊在未來的移動方向

OK. Well, (as)studying the movements of the plates can tell us about the location of the continents in the past, it can conceivably tell us about their location in the future too, right? So, in recent years, some geologists have used plate tectonic theory to make what they call geopredictions. Geopredictions are guesses about what Earth’s surface might look like millions of years from now.

So, we know how certain continents are currently moving. For example, the continents of Africa has been creeping north toward Europe. And Australia has been making its way north too, toward Asia. 以例子先說明現(xiàn)在各個州的板塊移動方向，尤其強(qiáng)調(diào)了美洲的移動方向。

Does anyone know what’s happening to the Americas? I…I think we’ve talked about that before. Lisa?

They are moving westward, away from Europe and Africa. Right?

Right. And what makes us think that?

The Atlantic Ocean floor is spreading and getting wider, so there is more ocean between the Americas and Europe and Africa.

OK. And why is it spreading?

Well, the seafloor is spilt. There is a ridge, a mountain range that runs north and south there. And the rock material flows up from Earth’s interior here, at the split, which forces the two sides of the ocean floor to spread apart, to make room for the new rock material. 從老師和學(xué)生簡單的回答中我們可以總結(jié)出美洲現(xiàn)在的移動方向

Good. And that means, over the short term…uh… and by short term I mean 50 million years, that’s a blink of the eye in geological time. Um…over the short term, we can predict that the Americas will continue to move westward, farther away from Europe, while Africa and Australia will continue to move northward. 并且老師總結(jié)說over the short term美洲是往西邊移動的，那這種說話的方式就給了我們一個提示：一定會對長期的進(jìn)行描述

But what about over the long term? Say 250 million years or more. Well, over that length of time, forecasts become more uncertain. But lots of geologists predict that eventually all the continents, including Antarctica, will merge and become one giant land mass, a super continent, one researchers calling Pangaea Ultima, which more or less means the last super continent. 緊跟著后面就解釋了長期的移動方式。

Now, how that might happen is open to some debate. Some geologists believe that the Americas will continue to move westward and eventually merge with East Asia. This hypothesis is based on the direction the Americas are moving in now. But others hypothesize that a new super continent will form in a different way. They think that a new subduction zone will might occur at the western edge of the Atlantic Ocean. 順著剛才的內(nèi)容又提出了debate，并且我們可以想到既然是debate那么至少后面是會提出兩種理論的。首先第一種理論還是之前講到的往西邊移動

Paul, can you remind us what a subduction zone is?

Yeah. Um…basically, a subduction zone is where two tectonic plates collide. So if an ocean floor tectonic plate meets the edge of a continent and they push against each other, the heavier one sinks down and goes under the other one. So the…um…the oceanic plate is made of denser and heavier rock, so it begins to sink down under the continental plate and into the mantle.

Right. So the ocean floor would kind of slide under the edge of the continent. And once the ocean plate begins to sink, it would be affected by another force – slab pull. Slab pull happens at the subduction zone.

So to continue our example… As the ocean floor plate begins to sink down into the mantle, it would drag or pull the entire plate along with it. So more and more of this plate, the ocean floor, would go down under the continent into the mantle. OK?

So, as I said, currently the Atlantic Ocean floor is spreading, getting wider, but some researchers speculate that eventually a subduction zone will occur where the oceanic plate meets the continental plate of the Americas. If that happens, slab pull could draw the oceanic crust under the continent, actually causing the Americas to move eastward toward Europe and the ocean floor to get smaller. That is, the Atlantic Ocean would start to close up, narrowing the distance between the eastern edge of the Americas and Europe and Africa. So they form a single super continent.  最后給出的另一種理論就是像東邊移動了。

關(guān)于lecture的并列型結(jié)構(gòu)文章分析就先給大家解析到這里，如果同學(xué)們對于或是課程有任何的疑問，都可以