英语选修9人教新课标UNIT2浙江课件：热身和阅读（20张）.ppt

1、1.What is a navigator?Warming upA navigator explores new routes across the sea.2.What is the difference between a navigator and an explorer?A navigator explores the sea;an explorer discovers new places on land.navigatorseanautical instrumentsfind new islands or continentsNavigator is sb.who finds th

2、e position and plots the course of a ship by using maps and nautical instruments.explorerlanduse of compass and landmarksfind new places within an already identified island or continentExplorer is sb.who travels into or through a place in order to learn about it.1.How do you think seamen found their

3、 1.How do you think seamen found their way before modern accurate methods of way before modern accurate methods of navigation were invented?navigation were invented?Kept close to the shore,used nature such Kept close to the shore,used nature such as the sun,wind,birds,tide,etc,to help as the sun,win

4、d,birds,tide,etc,to help them,and used some of the instruments them,and used some of the instruments including a compass,astrolabe,etc.including a compass,astrolabe,etc.Discuss2.Which do you think was easier to work out:latitude or longitude?Latitude,because it was used to measure how far you had tr

5、aveled from land on a straight line.It was discovered a long time before longitude.3.Can you identify these early navigational instruments seamen used and explain how they are used?1)compass(in ancient China)2)astrolabe3)sextant4)sea/nautical/marine chart4.Which ones do you think are still used 4.Wh

6、ich ones do you think are still used today?today?Sea charts are still used today.Sea charts are still used passastrolabesextanta bearing circlea bearing circle方位圆the first instrument to measure the suns position and the suns shadowa quadrant a special tool for telling the position of the ship in rel

7、ation to the sun and various starsan astrolabemeasure how high stars were above the horizonAlongitudelatitude an updated navigational instrument to measure the angle between two fixed points outside the shipsextanta nautical/sea chartComprehending1.Read the passage and answer the following questions

8、.1)What is the use of a bearing circle,astrolabe,quadrant or sextant?()What is the use of a compass?()A.To set the course of the ship B.To measure the position of the ship C.To measure the speed of the ship D.To tell the timeAB2)Why are speed and time important in 2)Why are speed and time important

9、in working out the longitude of a ship?working out the longitude of a ship?Speed and time are important in finding Speed and time are important in finding out the longitude of a ship because the out the longitude of a ship because the earth moves fifteen degrees westwards earth moves fifteen degrees

10、 westwards every hour.If you know your direction,every hour.If you know your direction,speed and time,you can work out the speed and time,you can work out the approximate longitude or change in your approximate longitude or change in your position in relation to the stars.position in relation to the

11、 stars.3)Why is the position of the sun and various 3)Why is the position of the sun and various stars useful for working out latitude?stars useful for working out latitude?The position of the sun and stars are The position of the sun and stars are useful for working out latitude because useful for

12、working out latitude because they are fixed points in the sky and their they are fixed points in the sky and their movements in relation to the earth are movements in relation to the earth are already known.So they can be used to already known.So they can be used to measure a ships position.measure

13、a ships position.2.2.Suppose you were a sea captain Suppose you were a sea captain aiming to sail round Africa.Discuss aiming to sail round Africa.Discuss in groups:in groups:1)What skills would you seek in your 1)What skills would you seek in your sailors?sailors?2)What problems would you anticipat

14、e for 2)What problems would you anticipate for this journey?this journey?3.Read the passage again 3.Read the passage again and use the information to and use the information to analyseanalyse the navigational the navigational skillsskills.1.To find the ships position at sea a sailor 1.To find the sh

15、ips position at sea a sailor used used the North Star and the sun.the North Star and the sun.2.A sailor knew that land was nearby if he 2.A sailor knew that land was nearby if he saw _saw _._.3.Sailors used 3.Sailors used _to increase their speed._to increase their speed.fresh seaweed,nesting birds

16、returning fresh seaweed,nesting birds returning home in the evening or foghome in the evening or fog sea currents or tides and sea currents or tides and windswindsUsing nature4.There were two methods to find longitude:4.There were two methods to find longitude:1)_ 1)_ 2)_ 2)_measuring time and speed

17、measuring time and speedcompass and complicated mathematical compass and complicated mathematical tablestablesUsing instrumentscategory itemscategoryItemsClothesshoesHygieneToolsbeddingMedicinesWhat would you need for a weeks journey across the North Sea to England?shirt,trouserssoapblanketwaterproof bootsknife,scissorssea-sick tablets,