外研版一年级起点（初中二年级）八年级英语下册We have not found life on any other planets yet._课件1.ppt

1. Scientists think that there has been life on the earth for hundreds of millions of years. 科学家们认为地球上的生命已经有上亿年的历史。 hundred前加基数词，表示“一百、二百、三百……”，hundred要用单数形式；hundred与of连用表示“数百”时，hundred要用复数形式，即hundreds of。hundreds of millions of表示“数亿，上亿”。 例如： There are eight hundred students in our school. There are hundreds of people in the park. We planted _____ trees last year. A. hundreds of B. hundred of C. five hundreds D. five hundred of thousand, million, billion和hundred的用法相同。 Practise 2. None of them has an environment like that of the earth… 没有一颗拥有和地球一样的环境…… Why has no one communicated with us? 为什么没有人和我们联系呢？ none 指三个或三个以上的人或物中“没有一个”，其后常接“of + 名词 / 代词”，后面动词单复数形式均可。 no one表示“没有人”，作主语时，谓语动词常用单数形式。 We rang several times, but no one answered. 我们按了几次铃，但没有人来开门。 None of us has / have been to Sanya. 我们都没去过三亚。 — I’m hungry. Is there any bread in the fridge? — _____, but we have cakes. Would you like to have one? A. Some B. Much C. None D. Nothing Practise 3. However, no spaceship has travelled far enough to reach other stars in our Galaxy. 然而，还没有任何航天器能到达银河系里的其他恒星。 He is not old enough to join the army. 他年龄太小，不能参军。 We have enough time to finish the work. 我们有充足的时间完成这项工作。 enough作副词，修饰形容词或副词时放在被修饰词后面；enough作形容词，修饰名词时常放在被修饰词之前。如： 4. With so many stars in the universe, are we alone, or is there life out there in space? 宇宙中有这么多星球，我们是孤独的吗？抑或太空中还有其他生命存在呢？ With so many things to do, we have no time to play. 要做的事情这么多，我们都没时间玩了。 这里with so many stars in the universe是介词短语，在句中作状语。类似的例子还有： The woman stood there with her hands in the pockets. 那个女士站在那里，手插在口袋里。 Practise — Why do you always sleep ______? — Because I’m afraid of the dark. A. by yourself B. with the door open C. with the window open D. with the light on What have the scientists just received? (a message from one of our spaceships) Look at the picture from a science story for children and answer the questions. They’ve just received a message from one of our spaceshi