Unit7 Section4课件-2025-2026学年沪教版 英语八年级上册

Focusing on culture Cross-curricular connection* Secion4 Extending and developing competencies Focusing on culture Warm-up:Work in groups and brainstorm. 1.What is this? It is a tree trunk. 2.Look at the picture.What do you think these circles mean? scar from forest fire first year growth first year growth rainy season rainy season dry season dry season scar from forest fire 329 The memories of trees 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. 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! The memories of trees 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. s 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 leam 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 10 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. Scientists also look at tree rings to study natural disasters.For first year growth is example,sometimes there is a rainy season black area on a tree ring.This dry season usually means there was a forest scar from fire.If scientists count the rings forest fire from the black area,they can answer 20 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 pattems to learn the age of old buildings.Nowadays,they can even look at the chemistry of each tree ring to figure out exactly when 25 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! Sesion4 Extending and developing competencies rocusily oI心uiture The memories of trees Reading:Read the article and 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 answer the questions. 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 1. What is the main idea of the article? rings to tell the age of the tree.They also study tree rings to leam about the climate and the environment.Tree rings are a record of the climate.Some 2. What are tree rings,and why are they called rings are quite wide.This is a good sign as it means the tree grew well and the“memories of trees” 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. 3. How do tree rings help us understand the past? Thanks to this,scientists can look at the tree ring patterns to learn about climate change in a particular place. 4.How can scientists tell the age of a tree by Scientists also look at tree rings to study natural disasters.For first year growth looking at its tree rings? s example,sometimes there is a rainy season- 5. What do wide tree rings show? black area on a tree ring.This dry season- usually means there was a forest scar from 6. What do narrow tree rings mean? fire.If scientists count the rings forest fire from the black area,they can answer 7. What does a black area on a tree ring mean? difficult questions,such as "When did the fire happen?"and"How common are forest fires?" 8.How do tree rings help us understand human Tree rings can also help us understand human history.For example,scientists history? can use tree ring pattems to learn the age of old buildings.Nowadays,they can even look at the chemistry of each tree ring to figure out exactly when s 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! Sesion4 Extending and developing competencies Focusing on culture Reading:Read the article and answer the questions. 1.What is the main idea of the article? Tree rings can tell us things about the past. 2.What are tree rings,and why are they called the "memories of trees"? 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? 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 toto tell the age of old buildings Sesion4 Extending and developing competencies Focusing on culture Reading:Read the article and answer the questions. 4.How can scientists tell the age of a tree by looking at its tree rings? Scientists can tell the age of a tree by counting the rings inside the tree trunk. 5.What do wide tree rings show? A wide tree ring shows that the tree grew well that year.This happens when the tree gets enough sun and rain. 6.What do narrow tree rings mean? 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. Sesion4 Extending and developing competencies Focusing on culture Reading:Read the article and answer the questions. 7.What does a black area on a tree ring mean? 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. 8.How do tree rings help us understand human history? 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 1021CE Sesion4 Extending and developing competencies 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 count the rings to tell tell the age of the tree the age of a tree. are a record of climate (cientists look at the tree ring patters to leam Tree rings change about climate change in a particular place. ( provide information Scientists look at tree rings about natural disasters to study natural disasters. help us understand (Scientists use tree ring patterns to human history learn the age of old buildings. Sesion4 Extending and developing competencies Focusing on culture Scientists have long studied tree rings.This branch of science is called dendrochronology.Experts in this field use tree rings Notes to learn more about our world.They compare tree rings from different trees in the same area to collect data about the past.