资源简介

(共55张PPT)
Unit 7
The secret of memory
沪教牛津版八年级上册
Key question
主题范畴：
人与自我；人与自然
What have scientist learnt about memory
Section 4
Focusing on culture
聚焦文化
1.What is this
2. Look at the picture. What do you think these circles mean
scar from forest fire
first year growth
rainy season
dry season
It is a tree trunk.
Work in groups and brainstorm.
Lead-in
rainy season
dry season
scar from forest fire
first year growth
伤疤
Background information
年轮的应用
1. 计算树木年龄：根据年轮数量可推知树木年龄，用于考查森林的年代。
2. 了解当年气候条件：年轮宽窄能反映树木生长与当时当地环境气候的关系。气候条件优越时，树木生长好，木质部增加多，年轮较宽；反之则窄。
3. 判断方向：在北半球，树木年轮较疏的一面是南面，较密的一面是北面；南半球相反。
Pre-reading
contain
particular
chemistry
actually
ring
pattern
v. 包含；含有
adj. 专指的；特指的
n. 化学性质；化学
adv. 事实上；实际上
n. 戒指；铃声
n. 模式；图案
New words
Pre-reading
natural disaster
figure out
a record of ...
even though
自然灾害
弄懂；弄清楚
……的记录
尽管；虽然
New phrases
Reading
Human beings have the ability to remember the past. In one way, nature is also able to remember past events, and this helps scientists learn about the history of the Earth and humankind. Read the article about tree rings to learn what they can tell us.
Do trees have memories This may seem like a strange question, but trees can actually tell us things about the past. When a tree is cut down, you can see something special inside: rings. These rings are the memories of trees. Tree rings contain lots of secrets from the forest.
Every year the tree grows, there is a new ring. Scientists can count the rings to tell the age of the tree. They also study tree rings to learn about the climate and the environment. Tree rings are a record of the climate. Some rings are quite wide. This is a good sign as it means the tree grew well and was healthy. This happens when the tree gets enough sun and rain. When it doesn’t rain enough, the tree won’t grow as much, and the rings are narrow. Thanks to this, scientists can look at the tree ring patterns to learn about climate change in a particular place.
The memories of trees
Scientists also look at tree rings to study natural disasters. For example, sometimes there is a black area on a tree ring. This usually means there was a forest fire. If scientists count the rings from the black area, they can answer difficult questions, such as “When did the fire happen ” and “How common are forest fires ”
Tree rings can also help us understand human history. For example, scientists can use tree ring patterns to learn the age of old buildings. Nowadays, they can even look at the chemistry of each tree ring to figure out exactly when the tree was cut down. Thanks to this new method, a team of archaeologists discovered that a Viking village in Canada was built in the year 1021 CE.
It’s amazing that trees can tell us so much, even though they cannot talk!
　　
What is the main idea of the article
What are tree rings, and why are they called the “memories of trees”
How do tree rings help us understand the past
How can scientists tell the age of a tree by looking at its tree rings
What do wide tree rings show
What do narrow tree rings mean
What does a black area on a tree ring mean
How do tree rings help us understand human history
Reading
Read the article and answer the questions.
1. What is the main idea of the article
2. What are tree rings, and why are they called the
“memories of trees”
Tree rings can tell us things about the past.
Tree rings are the circles inside a tree trunk. Each year a tree grows, there is a new ring. The writer calls them the “memories of trees” because they contain information about the past. For example, they are a record of natural events and climate in the past.
3. How do tree rings help us understand the past
4. How can scientists tell the age of a tree by looking at its
tree rings
Scientists can look at tree rings and learn about past climate change and natural disasters such as forest fires. They can also use tree rings to learn about human history. For example, scientists can study old wood and find out when the tree was cut down. They can also use it to to tell the age of old buildings.
Scientists can tell the age of a tree by counting the rings inside the tree trunk.
5. What do wide tree rings show
6. What do narrow tree rings mean
A wide tree ring shows that the tree grew well that year. This happens when the tree gets enough sun and rain.
A narrow tree ring means that the tree did not grow as much that year. This can happen when a tree doesn’t get enough water.
7. What does a black area on a tree ring mean
8. How do tree rings help us understand human history
A black area on a tree ring usually means there was a forest fire. Scientists can count the rings from the black area to determine when the fire happened.
Tree rings help us understand human history by showing the age of old buildings and even revealing when trees were cut down. For example, scientists used tree ring patterns to discover that a Viking village in Canada was built in the year 1021 CE.
Tree
rings
tell the age of the tree
Scientists count the rings to tell the age of a tree.
are a record of climate change
provide information about natural disasters
help us understand human history
Scientists look at the tree ring patterns to learn about climate change in a particular place.
Scientists look at tree rings to study natural disasters.
Scientists use tree ring patterns to learn the age of old buildings.
2 Why are tree rings useful How do scientists make use of them Complete
the mind map below with the information from the article on page 110.
Scientists have long studied tree rings. This branch of science is called dendrochronology. Experts in this field use tree rings to learn more about our world. They compare tree rings from different trees in the same area to collect data about the
past.
Notes
/ dendr kr 'n l d /
树木年代学
3 Find the words and phrases in the article and match them with
their meanings.
(1) contain (line 4)
(2) particular (line 12)
(3) natural disaster (line 14)
(4) chemistry (line 24)
(5) figure out (line 24)
a used to refer to a specific
person or thing
b to discover the answer
c to have / hold something inside
d the chemicals that something is
made up of
e used to refer to an earthquake,
flood, forest fire, etc.
Discussion
Imagine you are a 100-year-old tree. What kind of “memories” would you have in your tree rings
Post-reading
4 What else do you know about tree rings Share with
your classmates.
Your ideas
1. They show when trees “Get Sick” or have other problems.
2. They “remember” air changes and pollution.
3. They tell how trees “Interact” with other living things.
4. They help police and archaeologists “Solve Mysteries”.
...
To learn about how scientists study tree rings, you can try to explore the following questions:
How do they find trees to study
What tools do they use
What have they discovered about the past
Why is their work important
Exploring more
Phrases
Find out the phrases from P110.
1. 砍伐 _________________
2. 了解 _________________
3. ……的记录 _________________
4. 自然灾害 _________________
5. 弄懂；弄清楚 _______________
6. 尽管；虽然 _________________
cut down
learn about
a record of ...
natural disaster
figure out
even though
Language points
1. This is a good sign as it means the tree grew well and was healthy.
句意：这是一个好迹象，因为这意味着这棵树生长得很好，而且很健康。
★ as 作连词，意为“因为”，引导原因状语从句；表示的理由较弱。
★ because强调直接的、根本的原因，语气最强，可用于回答 “why” 的提问。
★ since意为“既然；由于”，通常表示已知的、显而易见的原因。
2. Nowadays, they can even look at the chemistry of each tree ring to figure out exactly when the tree was cut down. 句意：如今，他们还能分析每圈年轮的化学成分，精确判断树木被砍伐的时间。
★ look at 意为“看”，look 相关常见表达还有：
look after 照顾；look up 向上看，查询；look for 寻找；look out 留神，注意。
★ figure out 意为“弄懂；弄清楚”，近义表达：find out；to figure out 在句子作目的状语。
3. It’s amazing that trees can tell us so much, even though
they cannot talk!
句意：树木虽然不会说话，却能告诉我们这么多信息，真是令人惊奇！
★ even though 意为“虽然；即使”，引导让步状语从句，从句可置于主句前或后，不与“but”连用。语气比 though /although 更强，带有 “出乎意料” 的感觉。
即学即练
( ) 1. She didn’t go to school ____ she was ill.
A. as B. because of C. so D. but
( ) 2. — Why didn’t Lucy go to the party last night
— ____ she had to finish her math homework.
A. As B. Because C. Since D. For
( ) 3. We need to ____ how to solve this problem before
the class meeting.
A. figure out B. look out C. look after D. look up
A
B
A
( ) 4. ____ he is only 12 years old, he can cook delicious
meals for his family.
A. Because B. Since C. Even though D. As
( ) 5. My mother asked me to ____ my little sister when
she went out to buy vegetables.
A. look up B. look after C. look for D. figure out
( ) 6. Please don’t ____ your phone while walking on the
street. It’s very dangerous.
A. look for B. look after C. look at D. look up
C
B
C
Practice makes perfect!
I. 根据首字母提示写单词，完成句子。
1. Is there a p_________ place you want to visit this weekend
2. My cousin studies c_________ at university because she
loves science.
3. The gift box c________ a toy car and a storybook.
4. I thought I lost my key, but a________ it was in my school
bag.
5. The tree r______ clearly show the growth of the tree over
the years.
articular
hemistry
ontains
ctually
ings
II. 根据汉语意思完成句子，每空一词。
6. 自然灾害过后，当地医院派遣了更多医生和护士去帮助受伤的人。
After the _______ _______, local hospitals sent more doctors and nurses to help the injured people.
7. 我花了 20 分钟努力弄清楚这道数学题。
I spent 20 minutes trying to _______ _______ this math problem.
8. 即使超市离家很远，妈妈还是走路去买新鲜蔬菜。
_______ _______ the supermarket was far from home, my mom walked there to buy fresh vegetables.
natural disaster
figure out
Even though
Cross-curricular connectionl
Psychology
跨学科链接 心理学
Scientists have done experiments to discover how memory works and why it fails. Let’s explore how we remember better.
科学家们通过实验发现了记忆是如何工作的，以及记忆失败的原因。让我们来探索一下如何才能更好地记忆。
Cross-curricular connection Psychology
Do you ever forget things you have studied
What do you think the graph below shows
The Forgetting Curve
德国心理学家艾宾豪斯在1885年提出了关于遗忘规律的艾宾豪斯遗忘曲线:
曲线规律：遗忘在学习之后立即开始。且进程不均匀，呈现先快后慢的特点。在记忆最初阶段遗忘速度最快，随后逐渐减慢，长时间后几乎不再遗忘。比如刚记完时记忆保留量为100%，20分钟后约剩58%，1小时后约剩44%，1天后约剩 33%，之后记忆保留量越来越少。
相关结论：理解了的知识记得迅速、全面且牢固，而无意义材料比有意义材料更难记忆和回忆，
应用启示：对抗遗忘，学习后需立即复习，后续复习时间间隔可逐渐增加，比如学习第一天后复习，三天后再复习，接着一周后复习等，要在发生遗忘前及时复习，把短时记忆转换为长期记忆。
背景知识
艾宾豪斯遗忘曲线
How much can you remember after 24 hours
Hermann Ebbinghaus was the first person to study learning and memory by carrying out an experiment on himself. Below are his findings:
Ebbinghaus’s work showed that:
... forgetting happens quickest in the first nine hours.
... the things we study longer and more carefully will remain in our memory longer.
... things close to the beginning and end of a list or series are remembered most easily.
... it is easier to relearn things forgotten, than new things.
... learning meaningless things is difficult. Things that make sense and have meaning are remembered about ten times longer than things that don’t.
... it is easier to remember things if we study them in many learning sessions over longer periods of time.
Ebbinghaus discovered a pattern in remembering.
He found that in the first hour he forgot things very
quickly. Although this slowed down, after about
nine hours, people forgot about 60 per cent of what
they tried to learn. Finally, he found that 24 hours
after studying, people had forgotten around two-
thirds of anything they tried to learn and remember. This is the well-known “forgetting curve”. It starts with a sharp drop, followed by a gentle curve! Ebbinghaus’s work encouraged scientists to explore memory further and it became a field of study. He also helped create proper methods for experimenting in psychology. These are still used to this day.
1. Who was Hermann Ebbinghaus, and what did he study
2. What is the “forgetting curve,” and what does it show
Read the article from a science magazine about some findings on memory.
Hermann Ebbinghaus was the first person to study learning and memory by doing experiments on himself.
The forgetting curve is a pattern that shows how quickly people forget information. It starts with a sharp drop in the first few hours, followed by a gentle curve over time.
3. What did Ebbinghaus discover about relearning forgotten information compared to learning new things
Ebbinghaus found that it is easier to relearn things that have been forgotten than to learn completely new things.
4. Why is it easier to remember meaningful things than meaningless ones
Meaningful things are remembered about ten times longer than meaningless ones because they make sense and have meaning.
5. How does studying over longer periods of time affect memory
If you study over long periods of time, in many learning sessions, it will be easier to remember things.
Discussion
1. Why is the forgetting curve important for students
It shows that it is important to review things. Unless we review what we have studied, we will quickly forget most of it.
2. How can Ebbinghaus’s findings help you improve your study habits
Ebbinghaus’s findings suggest that we should study in many sessions over time, focus on meaningful information, and review material within the first few hours to avoid forgetting.
Discuss the questions below.
(1) What can you learn from Hermann Ebbinghaus’s
findings
(2) Which finding do you think is the most helpful
Project 项目
Testing the memory techniques
There are many techniques that can help improve our memory. In this project, you will choose two difficult memory techniques and do an experiment.
Memory technique 1:
Memory technique 2:
Things to prepare:
A memory test e.g. a number or word recall test
A timer
Experiment:
Step 1 Find nine subjects for your experiment. You may select those of a similar age or those of the same sex to avoid the effects of age and gender.
Step 2 Have each subject take a memory test. This first test will tell how good their memory is before they use the memory technique, and the results of this test are called the pre-test score.
Part 1 Conduct a memory test
Step 3 Divide the subjects into three groups:
Group 1: three subjects using memory technique 1
Group 2: three subjects using memory technique 2
Group 3: three subjects using no memory technique
Step 4 The next day, have all subjects take the same memory
test again. Record their scores. The results of the
second test are called the post-test score.
First, analyse the data. Which memory technique was the most effective Prepare a short presentation about your findings.
Present your findings to the class.
Listen carefully to the other groups’ presentations and evaluate them .
Part 2 Group presentation
Part 2 Group presentation
A memory test
What 2 memory techniques did you test
Who were the subjects
What did the subjects do (firstly, secondly ...)
What were their scores
What do these scores show
How will you use these techniques when you study (if)
The two memory techniques our group tested are
__________ and _________. Nine students took part in the tests. They are all in Grade ______, so they are all about ______ years old. We divided the students into three groups of three.
Firstly, they took part in _______, and their scores were ______.
Secondly, Group 1 learnt Group _______; Group 2 learnt _______; Group 3 _______.
Then the next day, they took part in _______.
Their average scores were _______. It shows that _______.
I will try to use _______ when I am studying. For example, if I study _______, I can _______.
Part 3 Vote and reflect
In groups, vote for the best presentation and discuss the following questions.
Which memory technique is the most effective / useful Why
How can you use these techniques when you are studying Please give examples.
Wits corner 智慧角
The true art of memory is the art of attention.
— Samuel Johnson
记忆的真正艺术是专注的艺术。
— 塞缪尔·约翰逊
（英国作家）
More wits
1. Memory is the diary that we all carry about with us.
记忆是我们随身携带的日记。
2. The best way to remember something is to teach it to someone.
记住某事的最好办法就是把它教给别人。
3. Tell me and I forget. Teach me and I remember. Involve me and I learn.
告诉我，我会忘记；教我，我会记住；让我参与，我会学会。
In this class, we have learned
new words and expressions in the text.
the detailed information and the structure of the text.
some important language points in the text.
Summary
Self-assessment
How well do you know about this lesson Tick the boxes.
I understand the new expressions in the article. 口 口 口
I understand the detailed information about the article. 口 口 口
I know how to retell the article with key words. 口 口 口
I think I can use all language points correctly. 口 口 口
可参考作业布置如下：
Samples:
Homework
书面作业（可选） 创新探究性作业（可选）
1.复习短语和语言点。 小组合作，每组选择一个与树木年轮相关的研究主题（如“树木年轮与气候变化”“树木年轮与历史事件”等）。各组通过查阅资料、分析树木年轮图片等方式进行研究，并将研究成果制作成幻灯片进行展示。
THANKS

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