1. Now it is hard to visualize a map that does not feature north at the top， but this was not always so.
本句中it做形式主语（formal subject），to visualize a map……。是真正的主语（real subject）。用it 做形式主语， 主要是因为主语较长，谓语较短，于是不定式常放在谓语的后面。例如：
1）It is necessary to tell him the news as soon as possible.（尽快把这消息告诉他是很必要的。）
2）It took us 30 minutes to get there by bus.（坐公共汽车到那儿花了我们30分钟时间。）
3）It made us very angry to see him talk to the old man in such an impolite manner.（看到他以如此不礼貌的方式与那位老人谈话，我们非常气愤。）
4）How much did it cost you to send the parcel express？（速递这个包裹花了你多少钱？）
1） It is not easy to master a foreign language.
2） It is our honor to be present at this dinner party.
3） It was a mistake for us not to help them.
4） It is unwise of them to turn sown the suggestion.
Visualize是一个动词，意思是 imagine （想像）。在词汇部分我们讲到过－ize是动词后缀。常用在形容词后面构成动词，如：localize（局部化，地方化）， urbanize （城市化），nationalize （使国有化）， finalize（最后定下来）visualize 这个动词，我们在第四单元中已经学过，请把下面两个句子译成英语，注意使用 visualize：
1） I cannot visualize what is waiting for me.
2） He has been visualizing the wedding ceremony to be held at the church for the whole day.
……this was not always so中的 so 是个代词，意思是“如此，这样”，如：
1）――I think you made the wrong decision.
――Is that so？ （是这样吗？）
2）It is not necessary to find out why it is so.（去了解为什么如此是没有必要的。）
3）I believe so.（我相信是这样。）
2. The oldest known map in the accepted sense of the word was drawn about 3，800BC， and represents the river Euphrates flowing through northern Mesopotamia， Irag.
1）This is the most dangerous substance known to man.（这是人类已知的最危险的物质。）
2）It has become a well known holiday resort.（这儿已成为著名的度假胜地。）
in the…sense of the word 意思是“就这个词的…意义上而言”，如：
1）It is a miracle in the true sense of the word.（这是真正的奇迹。）
2）That is an adventure in every sense of the word.（那才叫冒险。）
1） He has a great sense of humor.（他很有幽默感。）
2） There is some common sense in what he says.（他所说的话有些道理。）
3） What's the sense of doing that since it is already late？（既然已经晚了，做那件事还有什么意义呢？）
4） She came to her senses after a blood transfusion. （输血之后，他苏醒过来。）
5） In a sense what he said is true.（在某种意义上说，他说的话是正确的。）
6） Her explanation doesn't make any sense.（她的解释讲不通。）
7） I cannot make sense of what has written.（她写的东西我弄不懂。）
3. This and others that followed it， were little more than rough sketches of localized features； it was not until many centuries later that the ancient Greeks placed the science of map-making on a sound-footing.
本句中的前一个it是代指上句中的the oldest known map. Little more than 的意思是 almost no more than（只不过是）。请注意下列句子中的little的意思：
1） He is little better than a bookworm. （他简直跟书呆子差不多。）
2） That is little short of open scorn.（那简直就是公然藐视。）
It was not until…that…。是一个常见的强调句型，意思是“直到…才”。如：
1） It was not until the cat emerged from behind the bushes that I noticed it.（直到猫从灌木后面出来，我才注意到它。）
2） It was not until he called me that I realized there was a meeting in the afternoon.（直到他给我打电话我才想起下午有个会。）
3） It was not until several weeks later that the stolen car was found.（几个星期以后那辆失窃的汽车才被找到。）
1） It was not until the 1960S that man realized the dream of landing on the moon.
2） It was not until yesterday that he was told the truth.
3） It was not until mother came to the kinder-garter to collect him that the boy stopped crying.
place sth. on a sound footing 意思是“把…置于坚实的基础上”。
4. The last great scientist of the classical period， he was the first to draw a map that was based on all available knowledge， rather than guess or imagination.
The last great scientist of the classical period， 在本句中做同位语，对主语he作进一步的补充说明。
Be based on 意思是“以……为基础”。
Rather than在本句中的意思相当于instead of “而不是”。
1）I have used some simple words rather than the difficult ones.（我用了一些简单词汇而不是难词。）
2）He bought two books rather than one.（他买了两本书而不是一本。）
3）Rather than go back on his word， he kept his promise.（他没有食言，而是言而有信。）
5. Given the state of knowledge of those times， he got things wrong， ……
1）Given the poor working condition， you cannot expect the workers to be very efficient.（考虑到工作条件差，你不能指望工人们的效率很高。
2）Given the bad weather， we have to change our plan.（基于天气不好，我们得改变计划。）
1）The times are different， women are now equal to man.（时代不同了，现在男女平等了。）
2）In modern times， the development of science and technology is accelerating.（近代科学技术在加速发展。）
3）In the difficult times， many people died of hunger.（在那限难时世，许多人因饥饿而死。）
6. …since Ptolemy had calculated wrongly the size of the Atlantic and was unaware that the pacific ocean existed.
1）Since so many people are absent， we'd better put off the meeting.（既然如此多的人缺席，我们最好将此会延期。）
2）I won't blame you since you know nothing about it.（既然你对此一无所知，我就不会怪你。）
Unaware与aware一样是形容词，其用法也与aware相同，be unaware of…， be unaware that…。
1）I was unaware of his presence.（我没注意到他在场。）
2）He was unaware that he had been followed.（他不知道他被跟踪了。）
7. The reason for this was that he decided to orientate the map in the direction of the pole star since Polaris was the immovable guiding light in which the voyagers of the era placed their trust.
主语+连系动词+表语从句。表语从句也可用where， why， how引导。如：
1） The reason for his absence was that he was ill.（他缺席的原因是他病了。）
2） That was why I hated it.（这就是我不喜欢这个的原因。）
3） That is how he cheated people.（他就是用这种方式骗人的。）
1） This is the question about which we had a discussion last night.（这就是我们昨晚讨论的问题。）
This is the question that we. Had a discussion about last night.
2） This is the fact on which we base our opinion.（我们的观点就是建立在这个事实之上的。）
This is the fact that we base our opinion on.
Trust在句中做名词用，place （put） trust in sb/sth 信任某人（某事）。
1）I don't have any trust in him.（我对他一点也不信任。）
2）Have some trust in the future everything will be OK.（对未来有点信心吧，一切都会好起来。）
3） The old lady placed great trust in her grandson.（那位老太太对她孙子非常信任。）
8. North at the top remained the accepted arrangement until the early Middle Ages， when the church began to interfere seriously with the advance of science.
本句中when引导一个由逗号把前面句子隔开的句子，其意思相当于at the time.如：
1） The party has been put off until next week， when we can get better prepared.（晚会被推迟到下周，那时我们能准备得更好些。）
2） We will wait have until 6， when the manager can spare us a few minutes.（我们在这儿等到6点，那时经理就能给我们几分钟了。）
1） Bad dietary habits often interfere with health.（不良的饮食习惯常常妨碍健康。）
2） The interests of the two countries do not interfere with each other.（这两国相互间没有利害冲突。）
9. Once again， north assumed its rightful place at the top of maps.
It has long been assumed that aggression is caused by male hormones.（长期以来，人们认定好斗是由男性荷尔蒙引起的。）
1）I assume the misunderstanding will be cleared up.（我认定这误会会消除。）
2）He assumed the report to be unreliable.（他猜那报告不可靠。）
3） Farmers will have a good harvest ， assuming that the weather is favorable.（假如风调雨顺，农民将会有好收成。）
4） Who will assume the costs of running a school？ （谁来负担开设一所学校的费用？）
5） He assumed a leading position last May.（去年五月，他担任领导职务。）
6） Hitler assumed power in 1933.（希特勒于1933年夺得政权。）
7） He assumed full control of the company.（他完全控制了这家公司。）
1. in the sense of 2. more than
3. be based on 4. rather than
5. attempt to do sth 6. in the form of
7. in search of 8. at the top
9. in the direction of 10. place trust in
11. interfere with 12. in accordance with
13. from…point of view 14. reliance on
Text B You Have a Choice
1. side by side
They are sitting side by side.
We walked side by side along the river.
2. be seated
Please be seated， I will fix you a cup of coffee.
The hostess was seated with the guests when I hurried in.
3. ahead of
The boy is running ahead of his classmates.
I believe we can finish the work ahead of time.
4. be certain of
I cannot be certain of the time of their arrival.
Can you be certain of the truth of his utterance？
5. bring about
The new policy is sure to bring about a lot of changes.
What Father said has brought about a profound change in his personality.
6. account for
This excuse cannot account for your absence.
Her explanation doesn't account for the failure.
7. regardless of
All of you will be given a chance regardless of your age and sex.
Regardless of which method you choose， the result will be the same.
8. make a difference
Whether he comes or not will not make any difference.
I hope my participation will make a difference.
9. lead to
Excessive smoking may lead to lung cancer.
The misunderstanding led to a bad quarrel.
10. pull out of
The train pulled out of the station at 10：00.
When do you think the car will pull out of the garage？
11. for sure
I don't know for sure who will be in charge of this department.
He couldn't tell for sure what was in the distance.
12. apply to
It is hard to apply the rule to real work.
It is necessary that the theory be applied to practice.
13. deal with
He is hard to deal with.
I have no idea how to deal with this situation.