30.As natural science treats of the mutual transformation,changes and development of various kinds of matter,it is of great tmportance for us to make a profound study of it so that we may control the phenomena of nature.
自于自然科学研究的是各种物质的相互转化、变化和发展,因而我们深入研究自然科学以便控制各种自然现象,这具有重大意义。(treat of..,"论述”。带逻辑主体for us的不定式短浯to make...nature作主语,it是形式主语。so that引导目的状语从句。be of..,“具有”。)
31.With irrigation came surplus food,which meant that large numbers of people were freed trom the land to pursue nonagrarian specialities—technological development,scholarship for its sake——and war。
随着有了灌溉,粮食就有了剩余,这就意味着大批人就可解脱出来从事农业以外的工作一发展工艺,研究其学问——甚至参加战争。 (with...“随着”,引导的短语作状语。
With the approach of sunset it became chilly,come surplus food是倒装语序,food是主语,came是谓语。which引导特种定语从句,指上句话。不定式to pursue..。war有结果状语的意味。)
32.First of all, Kepler found that each planet goes around the sun in a curve called an ellipse,with the sun at a focus of the ellipse· -