高中英語必修三第四單元重點

1、精選高中英語必修三第四單元重點、難點 Unit Four Astronomy: the science of the stars1、They were followed in time by land animals. 陸地動物準(zhǔn)時消滅。in time準(zhǔn)時；最終A stitch in time saves nine. 小洞不補，大洞尺五。 You will get used to it in time. 最終你會習(xí)慣的。易混辨析：in time和on time in time表示“準(zhǔn)時；最終”； 而on time表示“按時”。聯(lián)想擴展：in no time 馬上；馬上 at one time

2、曾經(jīng)；一度 at a time 一次 at any time 在任何時候 at times有時；間或 from time to time 有時即時活用： How often do you go to see your parents? - _.A. In no time B. After a while C. In a short time D. From time to time 答案：D2、They produced young generally by laying eggs. 它們以產(chǎn)蛋的方式生產(chǎn)后代。lay eggs 下蛋 How many eggs does you hen lay

3、 every week? 你的母雞每周下多少蛋？聯(lián)想擴展：lay the table 擺桌子 lay up 儲存；擱置 lay over 推遲 lay the blame on 責(zé)怪 lay the foundation 奠定基礎(chǔ) lay to 歸咎于 lay open 攤開；揭露 lay out 擺開；呈現(xiàn) lay aside 放在一邊；積蓄 lay down 放下；放棄 lay for 等候3、These animals were different from all life forms in the past, because they gave birth to young baby

4、 animals and produced milk to feed them.這些動物和以前的任何生物形式都不同，由于它們產(chǎn)仔并用奶水喂養(yǎng)它們。give birth to生產(chǎn)；產(chǎn)生 She gave birth to a healthy baby last night. 昨晚她生了一個健康的嬰兒。That century gave birth to many great men. 那個世紀(jì)產(chǎn)生了很多偉人。4、These animals were different from all life forms in the past, because they gave birth to youn

5、g baby animals and produced milk to feed them.這些動物和以前的任何生物形式都不同，由于它們產(chǎn)仔并用奶水喂養(yǎng)它們。feed vt. 用法歸納：（1）飼養(yǎng) If I am laid-off, I will feed some pigs. 假如下崗，我就養(yǎng)豬。Do you feed any pets at home? 你在家養(yǎng)寵物嗎？ 特殊提示：feed作“飼養(yǎng)”講時，等于raise 和keep。（2）喂養(yǎng) We feed grass to sheep. 我們給羊喂草。We feed sheep with grass. 我們用草喂羊。特殊提示：留意fee

6、d當(dāng)“喂養(yǎng)”講時動物和飼料的前后挨次關(guān)系以及不同介詞的用法。即時活用：1、He_ a lot of chicken_ his farm. A. rises; in B. keeps; on C. raises; in D. supports; on 2、 I have a very bad cold.- Well, have you ever heard of a saying which goes “_ a cold and starve a fever?”A. feeding B. to feed C. fed D. feed 答案：BD5、Finally about 2.6 millio

7、n years ago some small clever animals, now with hands and feet, appeared and spread all over the world.最終大約在兩百六十萬年前，一些有手有腳的小型聰慧動物消滅了，并且集中到世界各地。spread v.用法歸納：（1）傳播；傳開（vi.）Bad news spreads quickly. 壞消息傳的很快。Word spread that there was a variant virus of H1N1. 消息稱H1N1病毒已經(jīng)產(chǎn)生變異。（2）鋪開；開放(vt.) The bird sprea

8、d its wings and was about to fly. 鳥伸開翅膀預(yù)備要飛。She spread a new sheet over the bed. 她給床上鋪了一個新床單。（3）涂；抹(vt.) Please spread the paint evenly. 把油漆抹均勻。Its better for you to spread the honey on the bread. 你最好把蜂蜜抹在面包上。（4）伸展；延長（vi.） Xian is spreading to the north and the west. 西安正在向北向西延長。The forest spreads fr

9、om here to the foot of Qinling mountains. 森林從這兒延長到秦嶺山腳下。聯(lián)想擴展：spread out 伸開；散開；鋪開 spread over 掩蓋一片；持續(xù) spread with 在上涂抹即時活用：Soon the news _ across the whole country, _the people.A. spread; exciting B. spread; excited C. was spread; excited D. was spread; exciting 答案：A6、Thus, in their turn, become the

10、most important animals on the planet. 這樣，輪到它們成為這個星球最重要的動物。in ones turn輪到某人；接著 Please get on the bus in your turn. 該你上車了。聯(lián)想擴展：at every turn 事事；經(jīng)常 by turns 輪番 go for a turn 閑逛；除去兜風(fēng) on the turn 在變質(zhì) out of turn 不合時宜的 take a turn 轉(zhuǎn)彎 take turns 輪番 to a turn 恰好7、They are putting too much carbon dioxide int

11、o the atmosphere, which prevents heat from escaping from the earth into space. 它們向大氣層排放大量的二氧化碳，這阻擋熱量向外層空間釋放。preventfrom doing 防止/阻擋發(fā)生 We must prevent the news from spreading. 我們應(yīng)當(dāng)阻擋這個消息的傳播。Nothing can prevent him from going away. 什么也不能阻擋他離開。特殊提示：(1)這個句型中prevent還可以被stop或keep替代。(2)主動句中，prevent和stop后面的

12、from可以省略，keep后的from不能省略；被動句中三個詞后的from都不能省略。聯(lián)想擴展：prevent vt. 防止；預(yù)防；阻擋（1） 跟名詞或代詞 Man is finding ways to prevent natural disasters. 人類正在查找預(yù)防自然災(zāi)難的方法。Vitamin C is supposed to prevent colds. 據(jù)認(rèn)為維生素C能預(yù)防感冒。（2）跟動名詞Teachers now have no ways to prevent students listening to MP3 in class.老師們現(xiàn)在沒方法阻擋同學(xué)們上課聽MP3。H1N

13、1 flu prevented his coming to school. 甲流使他不能來上課。（3）prevention n.預(yù)防；防止 （4）preventive adj. 預(yù)防性的即時活用：1、We should do what we can to _ the Changjiang River_.A. stop; from polluting B. keep; from being polluted C. prevent; from polluting D. keep; being polluting 2、Nobody can stop the naughty boy _.A. from

14、 punishing B. being punishing C. from being punished D. to be punished 3、The heavy rain _ us starting out on time. A. kept B. prevented C. protected D. was stopped 4、It seems very difficult _.A. to stop the child to cry B. restraining the child to cry C. to keep the child from crying D. holding the

15、childs crying答案：B C BC8、So whether life will continue on the earth for millions of years to come will depend on whether this problem can be solved.所以，在將來幾百萬年時間里生命能否在地球上連續(xù)取決與這個問題能否得到解決。depend vi.用法歸納：（1） 依靠 We students are depending on our parents now. 我們同學(xué)現(xiàn)在在依靠父母。The town depends entirely upon touri

16、sm. 這個小鎮(zhèn)主要依靠旅游。（2）依靠；期望 I mainly depended on his helping, but he didnt turn up. 我主要期望他幫忙，但是他沒來。There was no bus now, so we had to depend on our legs. 現(xiàn)在沒有班車了，我們只有期望雙腿了。（3）由.打算;取決于Whether we will hold the sports meeting depends on the weather. 我們是否進行運動會取決于天氣。The price depends on the quality. 價格取決于質(zhì)量。

17、特殊提示：depend是不及物動詞，后面一般要跟on或upon。聯(lián)想擴展：It / That (all) depends. 視狀況而定 即時活用：1、Im planning to hold a party in the open air, but I can make no guarantees because it _ the weather.A. links with B. depends on C. connects to D. decides on 2、The meaning of the word is various _different situation. A. depends

18、 on B. depending C. depending on D. depended on 3、 Will you go with us to the National Park? - Well, it _. A. depending B. depends C. depends on D. is depended 4、How wide is the Yellow River? That _ from where to where. A. depends B. changes C. refers D. lies 答案：BCBA9、As a result of this event, a gr

19、eat dust cloud formed in the sky blocking out the sunlight.這個大事的結(jié)果就是，天空形成了一團團的灰塵，遮擋了陽光。block out vt. 封閉；遮擋 That wall blocks out all the light. 那堵墻把光都遮住了。Block out the unimportant part on the picture. 把照片上不重要的部分遮住。聯(lián)想擴展：block vt.（1）堵??；堵塞A big stone has fallen from the mountain and blocked the road. 一個

20、大石頭從山上掉下來堵塞了道路。The pipe of heat must be blocked up. 暖氣管子確定是堵住了。（2）阻礙；阻擋 The wet weather blocked our plan for a trip. 下雨阻礙了我們的出行方案。The other player tried to block my advance, but he failed. 另一個球員試圖阻擋我前進，但是沒檔住。10、Then we were off. 然后我們就動身。off(1) (和某些動詞連用)開；掉 The bird flew off. 鳥飛走了。 I must dash off. 我

21、必需馬上離開。(2)（作表語）走掉；動身走 Are you really off? 你真要走嗎？ I must be off now. 我必需要走。(3)（和某些動詞連用）下去 Cut the end off. 把頭切掉。 Mind you dont fall off. 當(dāng)心別掉下去。(4)距離多遠(yuǎn)（時間；空間）Summer is only a week off. 再有一個星期就到夏天了。 They live two blocks off. 他們離我們只有兩個街區(qū)。(5) 不工作；休息 The manager gave the staff a day off. 經(jīng)理讓員工休息一天。If you

22、 finish your work today, you can have tomorrow off. 假如你今日做完工作，我就讓你明天休息一天。11、I cheered up immediately and floated weightlessly around in our spaceship cabin watching the earth become smaller and the moon larger.我馬上感到興奮，由于失重我在太空艙里飄來飄去，我望著身后的地球越來越小，而前方的月球越來越大。 cheer up 感到興奮；感到興奮Cheer up! Things are not

23、 so bad as they seem. 別泄氣，事情不像看起來那么糟。 The good news has cheered him up. 12、If you are right, my mass will be less than on the earth because the moon is smaller and I will be able to move more freely.假如你正確，我的體重要比在地球上小，由于月球比地球小，這樣我就能更自如活動了。mass n. 一堆；一塊；一團In cold winter, the pond will become a solid m

24、ass of ice. 寒冷的冬天，池塘?xí)兂梢粔K堅硬的冰。I found a mass of concrete on the bed. 我在床上發(fā)覺了一塊水泥。聯(lián)想擴展：（1）a mass of = masses of 大量的；很多After harvest, we will have a mass of rice. 收獲以后，我們會有大量的水稻。 I have masses of work to do today.特殊提示：a mass of = masses of 表示“大量的；很多”時，既可修飾可數(shù)名詞，也可修飾不行數(shù)名詞。（2） the masses 群眾 The masses ar

25、e the true makers of history. 人民群眾是歷史的真正締造者。The party should rely on the masses. 黨應(yīng)當(dāng)依靠群眾。（3）in the mass 一般來說 The work is well done in the mass. 大體上說工作做得不錯。13、Walking does need a bit of practice now that gravity has changed. 由于引力變化了，步行都需要練習(xí)。now that既然 Now that you have arrived, lets start the meeting

26、. 既然你們到了，我們開會吧。14、After a while I got the hang of it and we began to enjoy ourselves.過了一會兒我就理解了，我們就開頭盡情的玩耍。get / have the hang of 學(xué)會使用；懂得I cant get the hang of his speech. 我們有弄懂他講演的意思。The new machine is very easy to operate, you will soon get the hang of it.聯(lián)想擴展：give a hang about 對有愛好 I dont give a

27、hang about pop music. 我對流行音樂沒愛好。15、We watched, amazed as fire broke out on the outside of the spaceship as the earths gravity increased.我們驚異的看著，隨著地球引力的增加，宇宙飛船的外層燃燒起火。break out用法歸納：（1） 爆發(fā) The economic crisis broke out first in the United States. 經(jīng)濟危機首先在美國爆發(fā)。The First World War broke out in 1914. 第一次世

28、界大戰(zhàn)在1914年爆發(fā)。（2）突然發(fā)生 Flu usually breaks out in winter. 流感一般發(fā)生在冬季。A big fire broke out in the factory last night. 昨晚工廠發(fā)生大火。（3）突然大聲 People listening to the joke broke out laughing. 聽笑話的人突然大笑起來。聯(lián)想擴展：breakup 結(jié)束；拆開 break down 出故障；失?。簧眢w垮了 breakdown打到；破壞；消退break off斷開；折斷；中斷 break in闖入；打斷；插話 break into 強行進入；打斷 break through 沖過；克服；戰(zhàn)勝 break up 驅(qū)散；分開；放假即時活用：News reports say peace talks between the two countries have _ with no agreement reached.A. broken down B. broken out C. broken i