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.

come into being ^开始存在

To be or not to be, that is the question. — William Shakespeare 'Hamlet'

• I think therefore I am. — René Descartes

the advent of sth. / sb. ^{某事/某人的出现（重大事件、重要人物）}

• The advent of the steam engine heralded the beginning of a new era.
• The advent of the internet has changed the way we communicate. ^{互联网的出现改变了我们的交流方式。}
• The advent of the new CEO brought significant changes to the company. ^{新任CEO的到来给公司带来了重大变化。}

with the evidence began to accumulate ... ^{With 是介词，后面需要跟名词，不能直接跟句子。}

Recent scientific evidence seems to indicate that this assumption is incorrect.

indicate ^{v. 表明，表示}

• I shook my head and held up five fingers indicating that I was willing to pay £ 5.
• A survey of retired people has indicated that most are independent and enjoying life. ^{一项对退休人员的调查表明，他们中的大部分人生活自立而愉快。}
• Our vote today indicates a change in United States policy.  ^{我们今天的投票表明了美国政策的变化。}

Historians have long been puzzled by dots, lines and symbols which have been engraved on walls, bones, and the ivory tusks of mammoths.

be puzzled by ... ^{对...感觉迷惑不解}

• She was puzzled by the strange message.^{她对那条奇怪的信息感到困惑。}

造句：Doctors have long been puzzled by the rare skin condition. ^{医生们长久以来对这种罕见的皮肤病感到困惑。}

ivory ^{n.象牙，（其他动物的）长牙；象牙制品(不可数名词)}

• three ivory tusks ^{三根象牙(转为可数)}
• ivory tower ^象牙塔

The nomads who made these markings lived by hunting and fishing during the last Ice Age which began about 35,000 B.C. and ended about 10,000 B.C.

live by doing sth. ^{做某事为生}

• It has been said that everyone lives by selling something.
• He makes a living by teaching music. ^{他以教音乐为生。}
• They live by fishing in the local rivers. ^{他们靠在当地河流捕鱼为生。}

age ^{An age is a period in history. 时代}

•  ...the age of steam and steel.  ^{…蒸汽与钢铁时代。}
• the Ice / Stone Age ^固定搭配
• the modern age
• the computer age

造句：Laozi, legendary founder of Daoism, lived by taking charge of the royal library during the late Spring and Autumn Period which began about 600 B.C. and ended about 500 B.C. ^{传说中道教的创始人老子，生活 在大约公元前6世纪至公元前5世纪春秋时代的晚期，靠掌管国家图书馆为生。}

By correlating markings made in various parts of the world, historians have been able to read this difficult code.

in various parts of the world ^世界各地

• Cooked in wine, snails are a great luxury in various parts of the world.
• At present, they are visiting all parts of the country.
• ... tourists have been coming from all parts of the country to see it.
• Haroun Tazieff, the Polish scientist, has spent his lifetime studying active volcanoes and deep caves in all parts of the world.
• He's only forty-one years old,and he has already been to nearly every country in the world.
• ...the famous clock which can be heard all over the world on the B.B.C.

They have found that it is connected with the passage of days and the phases of the moon.

the phases of the moon ^{月相（圆缺）}

• wax and wane ^{周期性变化}

With joy and woe people meet and part ^{人有悲欢离合}
With light and shade the moon waxes and wanes^{月有阴晴圆缺}
Since time immemorial it's been unchanged ^{此事古难全}
Would that we could live a long life ^{但愿人长久}
And together share the moonlight though thousands of miles apart ^{千里共婵娟}

It is, in fact, a primitive type of calendar.

It has long been known that the hunting scenes depicted on walls were not simply a form of artistic expression.

They had a definite meaning, for they were as near as early man could get to writing.

definite ^{adj.清晰的，明晰的；确定的，不会改变的；肯定的，一定的}

• a definite answer
• a definite meaning
• definite article ^{定冠词（The）}

get to doing sth. = start doing sth. ^{开始做某事}

• He got to thinking that it was all his fault.
• Once we got to cooking, we realized we were missing some ingredients.^{一旦我们开始做饭，就意识到缺少一些食材。}
• She started studying as soon as she got home.^{她一回家就开始学习(start doing sth.)。}

It is possible that there is a definite relation between these paintings and the markings that sometimes accompany them.

accompany ^{v.陪伴，陪同；伴随}

• Having left the bag in the hall, I accompanied Robert into the living room.
• The disease is accompanied by sneezing and fever.

It seems that man was making a real effort to understand the seasons 20,000 years earlier than has been supposed. ^主系表

make an effort to do sth. ^{努力做某事}

• He made an effort to finish the project on time. ^{他努力按时完成项目。}