外研版(2019)高中英语选择性必修第一册 Unit 5 Revealing nature Using language课件(19张ppt)

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名称 外研版(2019)高中英语选择性必修第一册 Unit 5 Revealing nature Using language课件(19张ppt)
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资源类型 教案
版本资源 外研版(2019)
科目 英语
更新时间 2021-05-13 23:19:26

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Past perfect
Using language
Past perfect
1 表示在过去的某一时间或某一动作之前完成的动作或存在的状态。即“过去的过去。”
Before we got to the train station, the train had already left.
Before I could say “thank you”, he had run away.
2 表示从过去某一时间开始, 一直延续到过去的另一个时间的动作,常用的时间状语有 by then, by the end of , by the time.
By the end of last term, we had learnt 2000 English words.
They had lived there for ten years by then.
3 表示愿望,打算等的动词, 如hope, want, expect, think , mean, suppose, intend, plan 等后接从句时,一般用过去完成时表示本打算实现而未实现的愿望和计划。
I had intended to meet him at the airport, but I had an important meeting to attend.
I had hoped to take a holiday this year but I was not able to get away.
4 在句型 hardly…when 和no sooner…than 中, 主句用过去完成时,从句用一般过去时,表示”一…就…”.
Hardly had I left when it began to rain.
No sooner had he sat down than the telephone rang.
Look at the sentences from the reading passage and answer the questions.
1. In sentence (a), which action happened first, “suspected” or “evolved from a common ancestor”?
“evolved from a common ancestor.”
2. In sentence (b), which action happened first, “refused to believe” or “evolved from lower forms of life”?
“evolved from lower forms of life.”
3. What does the structure had done indicate?
It indicates the action happened before a certain past action.
Now look for more sentences with the past perfect tense in the reading passage, and summarise its use in your own words.
1. It was a young man who had left medical school without completing his degree.
2. ... he had recently received a letter from his father predicting that he would be “a disgrace to yourself and all your family.
3. After Darwin had spent some time in South America, his room on the ship was crowed with samples of the plants and animals he had
collected.
4. At that time, people believed that all species had appeared on Earth at the same time, and had not changed since.
5. It seemed their beaks had evolved according to what food was available on that particular island.
6. Over time, it had slowly evolved into many new species.
had made
Complete the paragraphs with the information from the given sentences.
1 a Natural disasters led to food shortages in the 1960s.
b Yuan Longping began to do research on hybrid rice.
c Yuan Longping developed a better type of rice.
Yuan Longping 1__________ to do research on hybrid rice because natural disasters 2_____________ food shortages in the 1960s. In the end, he 3_____________ a better type of rice.
2 a Gregor Mendel chose to study pea plants because their characteristics were easy to control.
b Gregor Mendel made important discoveries about genetics.
c Gregor Mendel died in 1884.
Gregor Mendel 4_______________ study pea plants because their characteristics were easy to control. By the time of his death in 1884, he 5____________ important discoveries about genetics.
began
had led to
developed
chose to
Yuan Long ping was born in Beijing in 1930. After he graduated from university in the early 1950s, he dedicated himself to the research of agriculture.
Yuan had the idea to create a new breed of rice in the 1960s. Since then, he has worked tirelessly to research and develop better rice breed.
In 1973 he and his collaborators managed to cultivate a hybrid rice species that was superior to many others. This species produced 20 per cent more rice per plant than the commonly grown varieties. For his achievements and contributions, Yuan is known as the “father of hybrid rice” and was awarded the Medal of the Republic in 2019.
Gregor Mendel(1822-1884) was an influential botanist. Mendel worked out the basic principles of heredity by experimenting with plants. In 1866, he published his findings, showing how invisible “factors”(now known as genes) are responsible for predictable visible traits.
As a result of his work, he became known as the “father of modern genetics”.
Complete the online encyclopaedia entry with the correct form of the words in the box.
Compete decline eat
Live introduce arrive
had lived
eaten
had introduced
competed
declined
arrived
Lonesome George was the last Pinta Island tortoise. He died in 2012. After George`s death, the Pinta Island tortoise was declared extinct.
The extinction of the Pinta Island tortoise blamed on humans. Before humans 1_________ on the island, the species 2_______________ in isolation and 3_____________ the plants that naturally grew there. George was discovered many years after their arrival, and by then humans 4_______________ new species that 5________________ for the food the tortoises ate. After goats in particular had been brought to the island, the Pinta Island tortoise population 6__________. Eventually, only George remained.
Biodiversity

Listen to the podcast and choose the statements that are made.
1 Biodiversity is important.
2 Bacteria are always harmful to humans.
3 Some species of bacteria are used in food production.
4 Many species of bacteria recycle dead organic matter.
5 Our immune systems are able to fight off all germs.
Listen again and complete the fact sheet.
thirty trillion
thirty-nine
trillion
made up of cells
bricks that are used to build houses
help with digestion
break down
Do you know about......?
Have you heard of ......?
Complete the boxes with the expressions from the podcast.
By the way......
Actually......
In fact,......
Speaking of which,…
Checking background knowledge
Adding information
What species are mentioned and what is special about them?

Two species are mentioned:the blue whale and the water bear.
The blue whale is the largest animal species on Earth, which can
grow up to almost 30 metres in length and weigh over 130,000 kilos.
The water bear is probably the toughest species, which can survive temperatures from 150?C to a below freezing -272?C.
The Galapagos Islands are renowned worldwide for their unique biodiversity. The Giant Tortoise Reserve on Santa Cruz 1_________ several species of giant tortoise that 2__________ the Galapagos Islands. The island is also home to the Charles Darwin Research Station, where 3_______ studies are carried out.
is home to
are native to
scientific
Complete the paragraphs with the correct form of the words and expressions in the box.
ancestor scientific be native to primitive habitat appearance be home to ecosystem
Mangroves are one of the coastal plants that grow on Isabela. They serve as the 4________________ for various birds and fish, and are very important to the 5________________.
habitats
ecosystem
Lguanas can be found on San Cristobal. They have a very special 6___________, with comb-like spines on their back.
appearance
primitive
ancestor
There is evidence that all the different iguanas have developed from more 7_____________ ones and share a common 8________________.
Look at the pictures of the species native to different regions of China.
Talk about biodiversity in China using the words and expressions in this section.
Thank you!