重点词汇：

　　1. forecast : 预报，预测

　　They forecast a large drop in unemployment over the next two years. 他们预测，在未来的两年中失

　　业率会大大下降。

　　Snow has been forecast for tonight. 预报今晚有雪。

　　同义词：predict v. 预测，预言

　　2.speculate: 思索，推测，投机

　　So far, the police can only speculate on the possible motives for the killing. 到目前为止，警方还只能

　　推测这起杀人案的动机。

　　Scientists have been speculating on the origin of life. 科学家们一直在思索生命的起源。

　　3.partial : a 偏袒的，偏爱的；部分的，不完全的

　　The judge’s decision should be partial to no parties. 法官的决定不应偏袒任何一方。

　　The police have only a partial description of the suspect. 警察对嫌疑犯的描述是不完全的。

　　4.up-to-date : 最新的，现代化的，直至目前的

　　They are up-to-date on the computer industry. 他们了解计算机工业的最新发展。

　　An up-to-date map 最新版地图

　　5.on the alert : 警戒，防备着(危险、意外或机会)

　　Passengers on buses should be on the alert against pick-pockets. 公共汽车上的乘客应提防扒手。

　　Nuclear-armed bombers were on the alert during the crisis. 核武装轰炸机在危机期间处于警戒状态。

　　(视频)

　　五.Text B重点句子：(句子下面的解释同划线部分链接)

　　1. They hope to develop an early warning system that can be used to forecast earthquakes so that lives

　　can be saved . 他们希望研究出一种能够用来预报地震的早期预警系统，以拯救生命。

　　该句中that引导的定语从句修饰an early warning system 。

　　so that 引导目的状语从句说明前边的复合句。

　　2. The nations that are actively involved in earthquake prediction programs include Japan, China, Russia,

　　and the United States.

　　定语从句中短语 be involved in … “参加，参与”

　　例如： All the children were involved in the school play. 所有的孩子都参加了学校排练的剧。

　　The four men were all involved in organizing and carrying out the murders. 这四个人都参与组织和实施

　　了这些谋杀案。

　　3. These networks are on the alert for warning signs that show the weakening of rock layers

　　that can precede an earthquake. 这些网络始终处于戒备状态，搜索地震前岩石可能松动的警告迹象。

　　第一个定语从句修饰warning signs

　　第二个定语从句修饰the weakening of rock layers

　　4. Scientists speculate that the amount of radon increases in the ground when rocks layers shift,

　　exposing new rocks , and thus more radon. 科学家推测， 当岩层位移时，露出新岩石，

　　地下氡的含量会增加，因此就产生更多的氡。

　　exposing new rocks , and thus more radon.分词短语作动词shift的结果状语

　　5. However, all the scientists agree that more data is necessary to prove that radon levels in water are

　　associated with the possible birth of an earthquake. 但是，所有科学家都同意还需要有更多的数据

　　才能证明水中氡含量与可能发生地震之间有着联系。

　　在宾语从句中又有一个that 引导的宾语从句

　　6. While this is a small start, it is still a beginning. 尽管这是一个小的开端，但毕竟还只是处于初始阶段。

　　while引导让步状语从句，意为“尽管，虽然” (本单元视频结束)