Listen to this 2 英语初级听力(MP3+字幕) 第36课(8)
日期:2017-08-21 05:59

(单词翻译:单击)

This process gives high-quality proteins, some of them better balanced for human consumption than natural vegetable proteins. It would take only 3% of today's petroleum output to provide the total protein needs of entire human race.

With the exception of luxury items, and the Russians, I've heard, have already started to export synthetic caviare, most foods will be factory-made in the next century. This will free vast areas of agricultural land for other purposes, living, parks, recreation, hunting, above all, for wilderness.

As a source of raw materials, the sea seems inexhaustible. Any element you care to mention is there, in solution or lying on the sea bed.

We will also be forced to use it for more and more of our water supply, through desalination techniques. I'm sorry to leave the sea so hastily, but space is a lot bigger and I must spend more time on that.

Our current ideas of space and its potentialities are badly distorted by the primitive nature of our techniques. To prove this, here is a statistic that will surprise you.

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