Module 3 Journey to space Unit 2 We have not found life on any other planets yet教材知識詳解

1、 3/3Module3 Unit2 教材知識詳解1. Scientists think that there has been life on Earth for hundreds of millions of years.科學(xué)家們認(rèn)為地球上存在生命已有上百萬年了。本句為含有think的主從復(fù)合句，即“主語+think+賓語從句”如：I think it is a good thing.我認(rèn)為它是一個好事情。(1)當(dāng)主句的謂語動詞是think, believe, suppose(猜測，認(rèn)為)等，而主句的主語又是第一人稱時，后面賓語從句的否定詞常要前移，即否定主句的謂語動詞。我們稱這類現(xiàn)象為“否

2、定轉(zhuǎn)移（前移）”。如：we dont think Tom is right.我們認(rèn)為Tom是不對的。(2)從句中使用了there be句型的現(xiàn)在完成時，其結(jié)構(gòu)為；There have/has been.如：Has there been an accident?有過一次事故嗎？(3) hundreds of意為“數(shù)以百計的”，用來表示一個不具體的數(shù)量或一個夸張的說法。hundred意思是“百”，當(dāng)它和具體的數(shù)詞連用時，hundred不能用復(fù)數(shù)形式，也不能在其后加of。類似的詞還有thousand, million, billion 等。如：There are about two hundred

3、students on the playground.操場上大約有兩百個學(xué)生。There are hundreds of students on the playground.操場上有數(shù)百個學(xué)生。2. It is impossible to imagine.它是不可能想象到的。本句屬于“Itis+adj.+ (for sb.+) to do sth.”的句式，其中to do sth.是真正的主語，it只是形式主語。如：It is important to learn about safety knowledge.學(xué)習(xí)安全知識是很重要的。本句中的impossible是形容詞，意為“不可能的”。如

4、：It is impossible to live on the moon.在月球上生活是不可能的。The sun and its planets are called the solar system.太陽和它的行星被叫作太陽系，are called是一般現(xiàn)在時的被動語態(tài)，意為“被稱為，被叫作”。如：The cartoon is called The Smurfs.這部卡通片叫藍(lán)精靈。4. However, no spaceship has travelled far enough to reach other stars in our Galaxy.然而，沒有宇宙飛船能遨游到足夠遠(yuǎn)，到達(dá)我

5、們星系中的其他恒星上。形容詞或副詞+enough to+動詞原形，意為“足夠可以”。如：He is old enough to take care of himself.他大了，能照顧自己了。They are very far away and their light has traveled for many years to reach us.它們離得很遠(yuǎn),它們的光到達(dá)我們需要很多年。這是一個由and連接的并列句。句中不定式to reach us是表目的的狀語。away表示距離時，其句型為：主語+be+數(shù)詞+metres/kilometres+away。如：The school is two kilometres away from here.學(xué)校離這里兩千米。6. With so many stars in the universe, are we alone, or is there life out there in space?宇宙中有這么多的星球，我們到