新概念3 Lesson55earth词汇和句型11-15
11. Imagine a star up to 20 times larger, brighter and hotter than our own sun.
想象一颗比我们的太阳还要大，亮，热20倍的星星。
up to sth.:
（1） as much or as many as a certain amount or number but not more 多达 ……
The Olympic Stadium will hold up to 80,000 spectators.
奥林匹克体育馆能容纳多达8万的参观者。
The temperature went up to 35℃.
温度高达35度。
（2）= up till
for the whole of a period until a certain time or date 直到……
Up to the time of his death, Richard Colson was one of the most notable figures in our town.
直到他去世时，Richard Colson成为本镇最著名的人物之一。
同义短语= Up to now,
Up to now, historians have assumed that calendars came into being with the advent of agriculture, for then man was faced with a real need to understand something about the seasons.
直到现在，历史学家们还认为随着农业的发明而日历也出现了。因为那时人们面对着理解季节变化的需求。
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12. Alternatively, if the star were small, the life-supporting planet would have to have a close orbit round it and also provide the perfect conditions for life forms to develop.
反之，如果恒星很小，维持生命的行星就要在离恒星很近的轨道上运行。而且要有极好的条件才能使生命得以发展。
alternatively adv. used to introduce a suggestion or to mention sth. different to what has just been stated 或者
The agency will make travel arrangements for you. Alternatively, you can organize your own transport.
代理商会帮你做好旅行安排，或者，你自己安排交通。
We could go to the Indian restaurant, or alternatively, we could try that new Italian place. the planet which supports life。
我们可以去印度餐厅，或者，我们可以尝试那家新的意大利餐厅。
13. But how would we find such a planet if there were such a planet?
如果真的有这样的星球，我们怎么发现它呢？
14. At present, there is no telescope in existence that is capable of detecting the presence of life.
现在，没有一台现存的望远镜可以发现生命的存在。
（1） in existence 存在
The organization has been in existence for 25 years.
这个机构存在25年了。
come into existence 开始存在
Scientists have many theories about how the universe first came into existence.
科学家们对于宇宙何时诞生的有很多理论。
（2）presence n. the existence of sb. or sth. in a particular place 存在
one’s presence
Her presence during the crisis had a calming effect.
在危机中，它的出现有着安定人心的效果。
We enjoy staring at them entranced as they go about their business, unaware (we hope) of our presence.
我们很高兴看着他们开心地进展工作，完全没有注意到我们的存在。
15. It is impossible to look for life on another planet using earth-based telescopes.
使用放置在地球上的望远镜是无法观察到其他行星的生命的。
-based:
（1） combines with nouns referring to places to mean sth. positioned or existing mainly in
the place mentioned, or operating or organized from that place 位于……
a Washington-based organization位于华盛顿的机构
land-based missiles陆地导弹
（2） used with some names to make adjectives describing the main substance in a product
主要成分为……
lead-based paints 主要成分为铅的涂料
carbon-based fuels主要成分为炭的燃料
