新概念英语4第三课：It is probably true to say that early climbers___

这里的两个句子其实是We still do和we all want a code to.因为两句中没有连词,所以才用分号隔开,分号的主要作用很简单,它常用于分离没有连接词连接的句子.
living in a world in which .这一部分不是独立主格,因为独立主格结构在句中的功能就相当于一个带有自己主语的非限制性状语从句,虽没有真正的主语和谓语动词,但又在逻辑上构成主谓或主表关系.
比如The meeting being over,all of us went home.开完会后我们都回家了.the meeting being over相当于when the meeting was over
而此句中的这一部分并为出现主语,所以实际上这一部分只是后面we all want a code .的状语部分,只不过提前了,所以用逗号隔开

人们喜欢野营的原因并不一定是想省钱.
necessarily 修饰so,并不是如此,后面的that they are saving money 补充说明so.
分开解释可能更容易理人们喜欢野营的原因并不一定是这个,他们并不一定是为了省钱（解释前面的这个）.

后面的逗号标错了,应该把it加上,superimposed upon it,

整篇的范文有些过了,背新概念一些重点的句子和段落吧.背这些的最重要的是积累素材,也就是写作的模版.背到滚瓜烂熟的时候句型和文章的结构也就印在你脑子里,写作文的时候会非常得心应手.背熟了一般记住的也就是里面最重要的结构,像"nothing can be compared with..","I had no other...than..."之类的.其他的没必要记,也不一定记得住.整篇范文没用的信息就更多了,有点费力不讨好的感觉.四还好些,三里面大多都是一段议论一段叙述,考试不会要求写记叙文的吧

some snakes manufacture a poison 蛇产生毒
是这句话的主干
different in every respect from that of others,是形容词词组做后置定语
修饰poison.在很多方面与其他不同的毒
as different as arsenic is from strychnine; and having different effects.
就像砒霜不同于马钱子碱,是方式状语
as different as arsenic is from strychnine,and having different effects.
and having different effects 是状语,逻辑主语是 strychnine
为什么用分号我也搞不清楚

这是给你最满意的答复,希望有用!Education is one of the key words of our time.A man without an education,many of us believe,is an unfortunate victim of adverse circumstances,deprived of one of the greatest twentieth-century opportunities.Convinced of the importance of education,modern states ‘invest’in institutions of learning to get back ‘interest’in the form of a large group of enlightened young men and women who are potential leaders.Education,with its cycles of instruction so carefully worked out,punctuated by textbooks----those purchasable wells of wisdom----what would civilization be like without its benefits?
So much is certain:that we would have doctors and preachers,lawyers and defendants,marriages and births----but our spiritual outlook would be different.We would lay less stress on ‘facts and figures’and more on a good memory,on applied psychology,and on the capacity of a man to get along with his fellow-citizens.If our educational system were fashioned after its bookless past we would have the most democratic form of ‘college’imaginable.Among tribal people all knowledge inherited by tradition is shared by all; it is taught to every member of the tribe so that in this respect everybody is equally equipped for life.
It is the ideal condition of the ‘equal start’which only our most progressive forms of modern education try to regain.In primitive cultures the obligation to seek and to receive the traditional instruction is binding to all.There are no‘illiterates’----if the term can be applied to peoples without a script----while our own compulsory school attendance became law in Germany in 1642,in France in 1806,and in England in 1876,and is still non-existent in a number of‘civilized’nations.This shows how long it was before we deemed it necessary to make sure that all our children could share in the knowledge accumulated by the‘happy few’ during the past centuries.
Education in the wilderness is not a matter of monetary means.All are entitled to an equal start.There is none of the hurry which,in our society,often hampers the full development of a growing personality.There,a child grows up under the ever-present attention of his parents; therefore the jungles and the savannahs know of no‘juvenile delinquency’.No necessity of making a living away from home results in neglect of children,and no father is confronted with his inability to ‘buy’an education for his child.