Unit 9 Human Biology Grammar 课件（共18张，内嵌视频）2024-2025学年高二英语北师版（2019）选择性必修3

(共18张PPT)
Focus on Language
The Perfect
完成时态
Unit 9 Human Biology
Learning objectives
By the end of this period, students will be able to:
1.understand the usage of The Perfect;
2.learn how to use the perfect tense in the exercise and writing.
Lead-in
Presentation
完成时 The Perfect
1. 定义
完成时表示一个完成的动作。用来表示现在、过去或者未来某个时间点已经或将会完成的动作。
2. 构成
主语+have (根据时态和人称变化形式)+动词过去分词
3. 类别
1）现在完成时 Present perfect
2）现在完成进行时 Present perfect continuous
3）过去完成时 Past perfect
4）过去完成进行时 Past perfect continuous
1. Present Perfect(现在完成时)
1. I have enjoyed working in this job.
2. She has thought about it for a long time.
3. They have all agreed that it is the best course of action.
我喜欢这份工作。
她已经想了很久了。
他们都已经同意这是最好的行动方针。
现在完成时的构成: have/has + v-ed
1. 定义
现在完成时表示过去的动作或状态持续到现在，对现在造成的影响，可能持续发生下去。
(1)表示动作发生在过去，到现在已完成，强调对现在造成的影响或结果，常与yet, already, just, before, lately等词连用。
(2)表示动作从过去某时开始一直持续到现在，还有可能继续下去，常同these days, recently, so far, in the last/past…, "for+时间 段"和"since+时间点"等连用。
2. 构成
主语+have/has+动词过去分词
2. Present Perfect Continuous(现在完成进行时)
1. I have been waiting for him for the past hour.
2. Ai has been studying all day.
3. She has been running in a lot of races recently.
现在完成进行时的构成: have/has been + v-ing
(and he still hasn't arrived)
(and she is still studying now)
(and she hasn't stopped this)
1. 定义
现在完成进行时表示动作从过去某一时间开始，一直持续到现在，或者刚刚终止，或者可能仍然要继续下去。
(1)表示动作从过去某时开始，一直延续到说 话时刻，还在继续进行或可能进行下去，常与 表示一段时间的状语连用。
(2)表示一个动作从过去某时开始，一直延续 到说话时刻刚结束。
2. 构成
主语+have/has+been+动词现在分词
3. Past perfect(过去完成时 )
1. When I arrived Jane had just left.
2. The play had already started when we got to the theatre.
3. By the end of June they had treated over 10,000 patients.
我到时简刚刚离开。
我们到剧场时戏已经开始了。
到六月底他们已经治疗了一万多病人。
过去完成时的构成: had + v-ed
1. 定义
过去完成时表示过去某一时间或动作之前已经发生或完成的动作，以及此动作对过去的某一点造成的影响。
2. 构成
主语+had+动词过去分词
4. Past perfect continuous(过去完成进行时 )
1. I had been walking around all morning before I found her.
2. We had been trying to find the right road for
nearly an hour before we finally spotted (看见) it.
3. They had been watching the series for three months.
过去完成进行时的构成：had been + v-ing
1. 定义
过去完成进行时表示动作从过去的过去开始一直延续到过去某个时间点。在过去某个时间点时，这个动作可能刚刚停止，也可能仍然在进行。
2. 构成
主语+had+been+动词现在分词
Practice
Identify the tense of the sentences and write the number in the correct columns.
1. Natural cloning has been going on for generations.
2. Gardeners have been using a form of cloning when they take a cutting from a plant ...
3. For years, there had been attempts to clone animals.
4. Cloning primates has been proved to be “much harder” than cloning other species.
5. Dr. Sun Qiang said they had been wholly devoted to the research ...
6. Dr. Sun Qiang said they had been taking care of more than 1000 monkeys 24 hours a day, 7days a week ...
Present perfect Present perfect continuous Past perfect Past perfect continuous
4
1,2
3,5
6
1.On Thursday, the Institute of Neuroscience announced it ________________ (clone) two monkeys using non-reproductive cells.
2. It is reported that researchers all around the world __________________ (conduct) tests on animals, such as mice and dogs, for many years but couldn't find a way to clone monkeys.
3. The news of the successful cloning ______________(attract) attention from around the world.
4. However, cloning primates ________________ (also raise) ethical concerns.
5. For example, some people ____________________ (discuss) issues concerning how clones will be treated in society.
had cloned
have been conducting
has attracted
have also raised
have been discussing
Complete the passage with the correct from of the words in brackets.
6. The cyclist___________________(perform) impossibly well for several competitions, raising the suspicions of the judges.
7. He____________________(represent ) his country at international events for over a decade and continues to impress everyone.
8. Scientists__________________(discover) even more ways to improve physical performance over the past ten years.
9. I ____________________(try) to qualify for the swimming team for three years, but I still can't quite make the cut.
10.He_____________(finish) five seconds earlier in the event, so she was chosen for the Olympic team.
have been performing
has been representing
have discovered
have been trying
had finished
Complete the passage with the proper form of the words in brackets.
On Thursday, the Institute of Neuroscience announced it 1.___________ (clone) two monkeys using non-reproductive cells. It is reported that researchers all around the world 2.____________________ (conduct) tests on animals, such as mice and dogs, for many years but couldn't find a way to clone monkeys. The news of the successful cloning 3.____________ (attract) attention from around the world. However, cloning primates 4.______________ (also raise) ethical concerns. For example,
some people 5.__________________ (discuss) issues
concerning how clones will be treated in society.
had cloned
have been conducting
has attracted
have also raised
have been discussing
Summary
Homework
单句语法填空
1.(2023·新高考Ⅱ卷)Since June 2017,right before the arrival of the two new pandas, Meng Meng andJiao Qing,I _________________ (help) the panda keepers at the zoo to feel more comfortable and confident speaking English.
2.(2024·浙江1月高考)Over the last two years,some supermarkets _________________ (start) selling chicken or salad in packs designed with two halves containing separate portions(份).
3.Up to now, he _________________ (select) chairman of the Students’ Union twice in our school.
4.During her stay in Hangzhou, Jenny tried almost all the local foods her friends _______________________ (recommend).
5.The cost of living_________________(go) up by ten percent before the government took any action.
6.No sooner had she got to school than she ___________(begin) to clean her classroom.
have been helping
have started
has been selected
had recommended
had gone
began