Book 9 Unit2 Warming up and reading.[上学期]

课件47张PPT。sailing the oceanwarming upWhat is a navigator?
What is the difference between a navigator and an explorer?A navigator explores new routes across the sea.A navigator explores the sea; an explorer discovers new places on land.navigatorseanautical instrumentsfind new islands or continentsNavigator is sb. who finds the position and plots the course of a ship, an aircraft, a car, etc, using maps and 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.Are they navigators or explorers?Zheng HeMarco PoloJames CookPre-reading1. How do you think seamen found their way before modern accurate methods of navigation were invented?Kept close to the shore, used nature such as the sun, wind, birds, tide, etc, to help them, and used some of the instruments including a compass, astrolabe, etc.2. Which do you think was easier to work out: latitude or longitude?latitude?longitude?Latitude, because it was used to measure how far you had traveled from land on a straight line. It was discovered along time before longitude.3. Can you identify these early navigational instruments seamen used and explain how they are used?
4. Which ones do you think are still used today?compassastrolabesextantsea/nautical chartreadingRead about what navigation was like before modern instruments were used.Sailing the oceansFast-reading to get the general idea.Page 1Read the passage and answer the following questions.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 timeBAreturning home in the evening or fog.fresh seaweed, nesting birds2. Use the information to analyze the navigational skills and write the answers in your own words.To find the ship’s position at sea a sailor use _______________________.
A sailor knew that land was nearby if he saw ________________________________.
Sailors used ____________________ ______ to increase their speed.the North Star and the sun.sea current or tides andwindsUsing nature Keeping alongside the coastline
Using celestial bodies
Using wildlife
Using the weather
Using the seaUsing celestial bodiesto plot the positionsto work out the latitudea special cloud formation indicates there is land close byUsing wildlifeIf seaweed was fresh and smelled strongly, the ship was close to land.Sea birds could be used to show the way to land when it was nowhere to be seen.Using the weatherfogTo help identify the position of a stream or river when…To direct their sailingFast-reading to get the general idea. Then answer the questions.Page 21. Why are speed and time important in working out the longitude of a ship?Speed and time are important in finding out the longitude of a ship because the earth moves fifteen degrees westwards every hour. If you know your direction, speed and time, you can work out the approximate longitude or change in your position in relation to the stars.2. Why is the position of the sun and various stars useful for working out latitude?The position of the sun and stars are useful for working out latitude because they are fixed points in the sky and their movements in relation to the earth are already known. So they can be used to measure a ship’s position.Read again and fill in the blanksThere were two methods to find longitude: 1. _______________________
2._______________________measuring time and speedcompass and complicatedmathematical tablesWrite down the working principles of the following instruments:Bearing circle:
Astrolabe:
Quadrant:
Sextant:to compare the height of the sun now with the position of the sun at midday.to compare the position of the ship in relation to some stars or the sun.a more precise form of the astrolabe, to measure how high stars are above the horizon, and compare that measurement with previous measurements.an updated version of the quadrant and so it was more accurate, to measure the angle between tow fixed pints outside the ship.horizonSun heightA Baring CircleBearing the sun--- height and azimuth(The marks were used to measure the shadow of the sun and its height and position in the sky.)DiscussSuppose your were a sea captain aiming to sail round Africa. 1. What skills would you seek in your sailors?
2. What problems would you anticipate for this journey?1. What skills would you seek in your sailors?The sailors would need to be excellent navigators, able to cope with both hot and cold weather, experienced in sailing through very bad weather and able to co-operate in a team.2. What problems would you anticipate for this journey?I would anticipate very hot weather (around the equator), cold weather (around Cape of Good Hope), very stormy seas (around the Cape), and problems with food and water, etc.What would you do if you came across the following problems during your voyage?wait till the storm is over, and then find your new position and return to your original courseuse knots to find your speed and work out your approximate longitudeuse the compass and the astrolabe, quadrant or sextant to find out your position, return to your former course.follow nesting birds to shore; look for special cloud formations or fog over streams to find landuse a compassmeasure your position using the sun or stars; look for sea birds, cloud formations, fog or seaweed to show that land is nearbyWhat would you need for a week’s journey across the North Sea to England?shirt, trouserssoapblanketwaterproof bootsknife, scissorssea-sick tablets,learning about languageDiscovering useful words and expressionsReplace the words underlined by ones of similar meaning from the reading passage.Seeing the dark clouds above him, George hurried for home.
Sailing a boat alone far away from the shore made Flora’s parents worry about her safety.
Clare, would you please put your bicycle next to the others in the shed?offshoreoverhead alongside4. “Why don’t you plot a more simple route with the smallest number of stops?” asked Mary.
5. Setting out on a long journey by sea with unskilled sailors would be dangerous especially if there were no modern navigational instruments.simplifiedvoyageseamenFind the words from the reading passage that are the opposite of these compound wordsanywhere
upload
inward
unreliable
land flower
strong pointnowheredownloadoutwardreliableseaweedshortcomingWrite down the words you know, which are related to navigation and sea.navigationsail, sailor, voyage, latitude, longitude, equator, horizon, captain, land island, nautical middles, explore, exploration…seaseaman, seaweed, seafood, shore, offshore, onshore, beach, beach-ball, seabed, sea-bird, seagull, sea shell, seaside, sea water, seasick, coast, coastline, tide, wave, current…Complete the following paragraph with the words below.precise outward nowhere awkward reference seaweed accelerate mercy randomly voyage alongside approximateSamuel the sailor was extremely good at plotting his course using the stars as a ________. One day he was determined to set out on a _______ across an unknown sea to an unknown continent. He set out with his instruments so he would not be at the ______ of the sea. He found on his ________ journey a rocky island. It seemed to be covered in nest. Suddenly, as Samuel looked, an enormous bird swooped down and picked him up as if referencevoyagemercyoutwardhe were a/an ________ parcel. It __________ its speed and rose straight up into the air so as to reach the _______ place on the rocks where its nest lay. Once there, it shook itself and threw Samuel in the _____________ direction of the nest. There seemed to be ________ to hide but then he noticed lots of _______ on his left and quickly hid under it. The bird landed nearby and pecked ________ at the rocks. Samuelacceleratedawkwardpreciseapproximatenowhereseaweedrandomlyrolled over swiftly and found himself at the edge of the cliff. He looked down slowly with a beating heart. Below him was his boat lying _________ the shore! “How lucky I am!” Samuel thought to himself. He then gave a mighty leap and landed in it. Once inside he could safely sail away.alongsideBye-bye!