仁愛版初三英語上冊全冊教案2
(1) forests have become deserts, so more and more sorts of animals and plants are disappearing.
(2) as a result, many rivers and lakes are now dead.
(3) too much harmful radiation from the sun passes through the hole and reaches the earth directly.
(4) it causes the level of the oceans to rise and the climate of the earth to change.
4. develop the students’ sense of environmental protection.
ⅱ. teaching aids 教具
圖片/小黑板
ⅲ. five-finger teaching plan 五指教學(xué)方案
step 1 review 第一步 復(fù)習(xí)(時間:4分鐘)
通過檢查作業(yè)，引導(dǎo)學(xué)生開拓思維，提出保護環(huán)境和水資源的具體措施，復(fù)習(xí)不定代詞和副詞。為學(xué)習(xí)新詞匯作準(zhǔn)備。
(檢查作業(yè)，并找學(xué)生匯報結(jié)果，引導(dǎo)學(xué)生如何保護水資源。)
t: how do you protect our environment and save water?
s1: everyone should plant more trees.
s2: we should do everything we can to save water.
s3: everybody should know the importance of forests.
s4: pass laws against water pollution.
s5: collect and reuse waste water.
…
step 2 presentation 第二步 呈現(xiàn)(時間:18分鐘)
教師通過日常對話，借助1a中的圖片，創(chuàng)設(shè)情景，導(dǎo)入新課，呈現(xiàn)新的詞匯。
1. (教師由日常對話，引出本課話題，呈現(xiàn)部分新詞匯。)
t: what’s the weather like today?
ss: it’s …
t: as we know, beijing often has sandstorms in spring. what causes the bad weather?
ss: cutting down too many trees.
(展示1a第二幅圖畫。)
t: yes. all over the world, people have cut down millions of trees. and trees become fewer.
(板書并要求學(xué)生掌握。)
millions of
t: cutting down too many trees causes the bad weather. how can trees affect the weather?
s1: they can keep water from running away.
s2: they can stop …
s3: …
t: yes. trees can stop the wind and water from taking the earth away.
(板書并要求學(xué)生掌握。)
take away
2. (繼續(xù)探討上述問題，引出新詞匯。)
t: anything else?
(如果沒有學(xué)生回答，繼續(xù)如下問題。)
t: what’s the air like in the forest?
ss: it’s fresh.
t: yes. why?
ss: (允許學(xué)生用漢語回答。)樹能吸收二氧化碳并釋放氧氣。
t: that’s right. trees can breathe in carbon dioxide and breathe out oxygen.
(展示1a第五幅圖。)please look at the picture.
(板書并要求學(xué)生理解。)
carbon dioxide: co2
oxygen: o2
t: where does co2 come from?
s4: animals’ breathing.
s5: burning oil. for example, cars and buses.
t: yes. they have polluted the air. carbon dioxide in the air has increased a lot. this has formed a “blanket” around the earth.
(板書并要求學(xué)生理解。)
blanket
t: the heat from the sun can’t escape, so the temperature is rising.