Warming up、Pre-reading、Reading、Comprehending评课稿

Unit 2

Sailing the oceans

当今航海技术达到前所未有的水平，那么你知道古代一些有关航海方面的仪器吗？

Sinan，the ancient Chinese compass

It was invented by Zhang Heng in the Han Dynasty.It is made up of a bronze foundation (青铜底盘) and magnetic spoon(磁勺) which is made of natural magnet，positioned right in the center of the foundation. The handle of the spoon points to the south，while the other side points to the north.When the Sinan

is in the still，the handle of the spoon points to the south because of the influence of

the terrestrial magnetism (地磁)．

Astrolabe

It has 17 stars listed as well as a map of the sky overhead (for 37 degrees) and the ecliptic (黄道)．The time of day or night is on the outside edge with noon at the top of the Astrolabe and midnight at the bottom.It comes with a carrying chain，a pouch，and a book on its use.The reverse side has a sight for measuring the elevations of the heavenly bodies. Sextant

The sextant is a navigational instrument for measuring the angle between the horizon and some object in the sky.First a sailor looks at the horizon through an eyepiece.At the see light from the sun or a star

reflected off a small mirror on top of the instrument，onto a second mirror and into the eyepiece. 1/5

The navigator can then see two images，the horizon and the sun side by side.He can then measure the angle between them on a scale at the bottom of the instrument.The scale goes from 0 to 120 degrees.An earlier instrument，called a quadrant，measured in angle in the same way but it could only measure angles from 0 to 90 degrees. Nautical chart

Nautical charts are maps of the depth of the sea and the currents of the oceans.They provide modern sailors with routes through the seas，rather like roads through the countryside.The information began to be collected in the nineteenth century and has continued to be updated ever since.These charts were not available to Captain Bligh or Zheng He. 两个诱思问题

1．What is the theory of the Sinan invented by Zhang Heng?

2．Why were the Nautical charts not able to be used by Captain Bligh or Zheng He?

【答案】

1．The influence of the terrestrial magnetism. 2．Because the information began to be collected in the nineteenth century. Section Ⅰ

Reading (Warming Up, Pre­reading，Reading & Comprehending) [语

言

基

础

自

测] Ⅰ.根据词性及英文释义写出单词的正确形式

1．

n．kindness；forgiveness 2．

n．activity of exploring 3．

adj.above one's head 2/5

4．

adj.at sea not far from land 5．

adj.made or done without any plan 6．

adj.difficult to use 7．

n．act of mentioning；act of looking at for information 8．

adj.light and that can be(easily) carried or moved 【答案】

1.mercy

2.exploration

3.overhead 4.offshore

5.random

6.awkward

7.reference

8.portable Ⅱ.短语填空

may well；at the mercy of；work out；be close to；the number of；compare with；in relation to；rather than 1．I prefer to walk there

take a bus. 2．The boat was

the rapid river. 3．This novel

become a classic. 4．

those who are suffering，we are better off. 5．I believe that you can

this problem by yourself. 【答案】

1.rather than

2.at the mercy of 3.may well

4.Compared with

5.work out [教

材

语

篇

细

研] Ⅰ.阅读P12－13课文内容，从三个选项中选择最佳答案

1．How many traditional methods used by seamen are mentioned in the passage? A．Four.

B．Five.

C．Eight. 2．The passage doesn't tell us whether skilled seamen used to use the

to judge his position at sea. A．North Star

B．sun

C．moon 3．By studying the winds，seamen could

．

A．judge the direction of the ship B．know how far away they were from their home C．tell the distance they had discovered 4．From the passage we can learn that

．

A．why early seamen wanted to sail the seven seas 3/5

B．there is useful information in an encyclopedia C．early sailors went exploring the seas using their skills and simple instruments 5．The purpose of the passage is to tell us

．

A．keeping a longitude of the coastline is the first and most useful form of exploration B．about the skills and navigational aids early seamen used while sailing the oceans C．the finding of latitude and longitude is a must to plot a ship's position on a map 【答案】

1.A

2.C

3.A

4.C

5.B Ⅱ.阅读P12－13课文内容，完成下列表格

Keeping alongside the The 1.

useful form of exploration.

coastline

Using nature help to Using celestial bodies North Star: At the North Pole it is at its2.

position；At the equator it is along the horizon.

Sun：The sailors could use the height of the sun to work out their 3.

.

Clouds：A special cloud formation indicates land close by. Seaweed：Sailors could Using 4

.

Using navigat­5.

by the colour and smell of seaweed.

Birds：Seamen could follow the birds which return to land to find land. Fog: Seamen used fog to 6.

the position of a the stream or river.

Winds：Seamen used winds to7.

their sailing.

Using the sea Finding Certain tides and currents could be used to carry ships to their destination.

Sailors knew a method of ional instruUsing ­ments to weather

help 4/5

longitude 8.

longitude using speed and time. The Bearing Circle: The first instrument to measure 9.

.

The Astrolabe：It gave the seamen the local time and Finding latitude allowed them to find their latitude at sea.

The

Quadrant:

It

measured

how

high 10.

were.

The Sextant: It proved to be the most accurate and reliable of these early navigational instruments. 【答案】

1.first and most

2.highest

3.latitude

4.wildlife

5.tell

6.identify

7.direct 8.calculating

9.the sun's position

10.stars Ⅲ.阅读P12－13课文内容，完成下面课文缩写

This reading explains how seamen 1.

(explore)the oceans and what kind of navigational instruments were used to sailors 2.

the seventeenth century 3.

they were navigating the open seas without seeing land.The 4.

(voyage) of travellers before the 17th century show that they were not 5.

the mercy of the sea even though they did not have modern 6.

(navigation) aids.The seamen could use celestial bodies, wildlife, the weather or the sea to keep 7.

the coastline.They could also use 8.

compass to help find the direction that the ship needs to go.They could use the 9.

(bear) circle to measure the sun's position and tell if they were sailing on their correct rather than a random course. While the astrolabe，the quadrant and the sextant could help give the seamen the local time and allowed them 10.

(find)their latitude at sea. 【答案】

1.explored

2.before

3.when

4.voyages

5.at

6.navigational

7.alongside

8.the

9.bearing

10.to find 5/5