外研版 (2019)Unit 5 Revealing nature图文课件ppt

这是一份外研版 (2019)Unit 5 Revealing nature图文课件ppt，共26页。PPT课件主要包含了Summary，break down等内容，欢迎下载使用。
① Lk at the sentences frm the reading passage and answer the questins.
1. In sentence (a), which actin happened first, “suspected” r “evlved frm a cmmn ancestr”? 2. In sentence (b), which actin happened first, “refused t believe” r “evlved frm lwer frms f life”?3. What des the structure had dne indicate?It indicates the actin happened befre a certain past actin.
Nw lk fr mre sentences with the past perfect tense in the reading passage, and summarise its use in yur wn wrds.
1. It was a yung man wh had left medical schl withut cmpleting his degree.2. ... he had recently received a letter frm his father predicting that he wuld be “a disgrace t yurself and all yur family.3. After Darwin had spent sme time in Suth America, his rm n the ship was crwed with samples f the plants and animals he had cllected.4. At that time, peple believed that all species had appeared n Earth at the same time, and had nt changed since.5. It seemed their beaks had evlved accrding t what fd was available n that particular island.6. Over time, it had slwly evlved int many new species.
Grammar: Past Perfect Frms
The past perfect is frmed using had + past participle. Questins are indicated by inverting the subject and had. Negatives are made with had nt.Statement: Yu had studied English befre yu mved t New Yrk.Questin: Had yu studied English befre yu mved t New Yrk?Negative: Yu had nt studied English befre yu mved t New Yrk.
Grammar: Past Perfect Uses
表示在过去某一时刻或某个动作之前已经发生或完成的动作或存在的状态。这个过去的时刻常用by, befre, until等引导的短语或时间状语从句来表示，也可以通过一个表示过去的动作或上下文来表示。By nine 'clck last night, we had finished mst f the wrk. She had learnt abut 500 English wrds befre she went t middle schl.
表示过去某一时间之前发生的动作或存在的状态一直持续到那时，并可能继续下去，常同由fr或since引导的表示一段时间的短语或从句连用。I had been at the bus stp fr 30 minutes when a bus finally came. She said she had made great prgress since she came here.
在含有定语从句的主从复合句中，如果主从复合句叙述的是过去的事，则先发生的动作常用过去完成时。She returned the bk that she had brrwed. The twins, wh had finished their hmewrk, were allwed t play badmintn n the playgrund.
过去完成时常常用在宾语从句(或间接引语)中，这时从句谓语表示的动作发生在主句谓语表示的动作(过去时)之前。I thught that I had seen him befre. I was sent t the village last mnth t see hw the develpment plan had been carried ut in the past tw years.
在含有时间、条件、原因、方式等状语从句的复合句中，若主从句动作的发生有先后顺序，动作在前的要用过去完成时，动作在后的要用一般过去时。I had finished cking dinner befre yu came back. I fund the lecture hard t fllw because it had started when I arrived.
want, hpe, mean, plan, intend等动词的过去完成时可以用来表示过去未曾实现的想法、希望、打算或意图，意为“本来……”。I had hped t be back last night, but I didn't catch the train. We had intended t cme and see yu.
过去完成时常用于某些固定句型：在“ n ”句型中， 主句用过去完成时，从句用一般过去时。I had n sner reached hme than it began t rain. ＝N sner had I reached hme than it began t rain. It was＋一段时间＋since从句(从句用过去完成时) 。 It was at least three mnths since I had left Beijing.
过去完成时常用于某些固定句型：It was the ＋(that)从句 (从句用过去完成时)。It was the first time that I had chatted nline in English. by the time＋表示过去的从句＋主句(过去完成时)。 By the time I gt t the statin, the train had already gne. by the end f＋表示过去的时间＋句子(过去完成时)。 By the end f last term we had learned 10 units.
过去完成时用于虚拟语气中，在wish, as if/as thugh, if, if nly, wuld rather sb. had dne sth.结构或从句中，常用过去完成时来表示与过去事实相反的假设。If he had caught the early bus this mrning, he wuld nt have been late fr class. I wuld rather she hadn't dne that.
Grammar: Difference frm the Simple Past Perfect
过去完成时在时间上强调“过去的过去”，而一般过去时强调过去某一特定的时间。They had arrived at the statin by ten yesterday. They arrived at the statin at ten yesterday. 在没有明确的表示过去的时间状语作标志时，谓语动词表示的动作发生的时间先后须依据上下文来判断：先发生的用过去完成时，后发生的则用一般过去时。She was very happy and her whle family were pleased with her, t. She had just wn first prize in the cmpsitin cmpetitin.
② Cmplete the paragraphs with the infrmatin frm the given sentences.
beganhad led tdevelped chse thad made
③ Cmplete the nline encyclpaedia entry with the crrect frm f the wrds in the bx.
arrived had lived eatenhad intrduced cmpeted declined
Cmpete decline eatLive intrduce arrive
④ Wrk in pairs. Act ut a rle-play using the infrmatin in Activity 3. One f yu will play the keeper f Lnesme Gerge, and the ther will play the reprter asking abut Gerge. Use the past perfect tense where apprpriate.
⑤ Listen t the pdcast and chse the statements that are made.
Bidiversity
1 Bidiversity is imprtant.2 Bacteria are always harmful t humans.3 Sme species f bacteria are used in fd prductin.4 Many species f bacteria recycle dead rganic matter.5 Our immune systems are able t fight ff all germs.
⑥ Listen again and cmplete the fact sheet.
made up f cells
bricks that are used t build huses
thirty trillin
thirty-nine trillin
help with digestin
⑦ Cmplete the bxes with the expressins frm the pdcast.
D yu knw yu heard f
By the fact, f which,…
Checking backgrund knwledge
Adding infrmatin
⑧ Read the passage and answer the questins.
What species are mentined and what is special abut them?What ther unusual life frms d yu knw f?
Tw species are mentined: the blue whale and the water bear.The blue whale is the largest animal species n Earth, which can grw up t almst 30 metres in length and weigh ver 130,000 kils. The water bear is prbably the tughest species, which can survive temperatures frm 150ºC t a belw freezing -272ºC.
⑨ Cmplete the paragraphs with the crrect frm f the wrds and expressins in the bx.
is hme t are native t scientific habitats ecsystem appearance primitive ancestr
⑩ Wrk in pairs. Lk at the pictures f the species native t different regins f China. Talk abut bidiversity in China using the wrds and expressins in this sectin. D nline research t find mre infrmatin.
Review past perfect tense.D further research n bidiversity in China and share yur ideas with yur friends.