PTE考生目前最大的问题之一就是练习题缺乏。除了有限的基本官方书（PLUS，Testbuilder, OG）之外，就没有题了。很多英语基础不是很扎实的同学很难找到练习材料。墨尔本文波雅思PTE培训学校专门为墨尔本，悉尼PTE考生准备了PTE练习的lecture 93篇。各位PTE同学可以练习阅读，练习记笔记技巧，可以练习复述，甚至可以练习describe image。废话少说，下面开始：
Today I want to talk about the Earth’s last major climatic shift, at the end of the last ice age. But first, let’s back up a moment and review what we know about climatic change in general. First, we defined “climate” as consistent patterns of weather over significant periods of time. In general, changes in climate occur when the energy balance of the Earth is disturbed. Solar energy enters the Earth’s atmosphere as light and is radiated by the Earth’s surface as heat. Land, water, and ice each affect this energy exchange differently. The system is so complex that, to date, our best computer models are only crude approximations and are not sophisticated enough to test hypotheses about the causes of climatic change. Of course, that doesn’t keep us from speculating. For instance, volcanic activity is one mechanism that might affect climatic change. When large volcanoes erupt, they disperse tons of particles into the upper atmosphere, where the particles then reflect light. Since less light is entering the system of energy exchange, the result would be a cooling of the Earth’s surface. Of course, this is just one possible mechanism of global climate change. In all probability, a complete explanation would involve several different mechanisms operating at the same time.
【生词摘录】
- climatic: adj. connected with the weather in a particular area 气候的
- ice age: one of the long periods of time, thousands of years ago, when icecovered many northern countries 冰川期,冰河时代
- consistent:adj.alwayshavingthesamebeliefs,behavior,attitudes,qualityetc(信仰、行为、态度、品质等)一贯的,一致的;始终如一的
- disturb:v.tointerruptsomeonesothattheycannotcontinuewhattheyaredoing by asking a question, making a noise etc 干扰,打扰;使中断
- radiate: v. if something radiates light or heat, or if light or heat radiates from something, it is sent out in all directions 辐射(光或热);(向四面八方)发射
- crude: adj. not developed to a high standard or made with great skill 粗制的
- approximation: n. [C]a number, amount etc that is not exact, but isalmost correct 概算,近似值
- hypothesis: n. [C]plural hypotheses, an idea that is suggested as apossible way of explaining a situation, proving and idea etc, which has notyet been shown to be true 假设,假说
- speculate: v. to think or talk about the possible causes or effects ofsomething without knowing all the facts or details 猜测,推测
10.disperse: v. if something disperses or is dispersed, it spreads over a wide
area(使)消散;(使)分散
11.cooling: n.[U]the process of becoming cooler; a falling temperature 冷却
