Warming up、Pre-reading、Reading、Comprehending优秀教案内容

Unit 2 Sailing the oceans

Part One: Teaching Design SAILING THE OCEANS READING Aims

To help students read about sailing the oceans

To help students learn about the predicate Procedures

Warming up by leaning about navigator What is a navigator? A navigator is the person onboard a ship responsible for the navigation of the vessel. On aircraft, the position may also be referred to as a flight officer. The navigator's responsibilities include planning the journey, advising the captain (or pilot) while en route, and ensuring that hazards or obstacles are avoided. What is exploration? Exploration is the act of searching or traveling for the purpose of discovery, e.g. of unknown regions, including space (space exploration), or oil, gas, coal, ores, water (also known as prospecting), or information.

Exploration has existed as long as human beings, but its peak is seen as being during the Age of Exploration when European navigators travelled around the world.

In scientific research, exploration is one of three purposes of research (the other two being description and explanation). Exploration is the attempt to develop an initial, rough understanding of some phenomenon. II. Reading for forms

Read the text SAILING THE OCEANS on page 12 to: cut/ the sentence into thought groups, blacken the predicative, darken the connectives and underline all the useful expressions. SAILING THE OCEANS We may well wonder/ how seamen explored the oceans/ before latitude /and longitude made it possible /to plot a ship's position/ on a map．The voyages of travelers/ before the 17th century /show that /they were not at the mercy of the sea /even though they did not have modern navigational aids．So/ how did they navigate so well? Read these pages/ from an encyclopedia．

Using nature to help

Keeping alongside the coastline

This seems to have been the first /and most useful form of exploration /which carried the minimum amount of risk．

Using celestial bodies

North Star At the North Pole /the North Star is at its highest position /in the sky, but at the equator /it is along the horizon．So /accomplished navigators were able to use it /to plot their positions．

Sun On a clear day /especially during the summer/ the sailors could use the sun /overhead /at midday to navigate by．They can use the height of the sun /to work out their latitude．

Clouds Sea captains observed the clouds /over islands. There is a special cloud formation /which indicates /there is land/ close by. Using wildlife

Seaweed Sailors often saw seaweed/ in the sea /and could tell /by the colour /and smell/ how long it had been there．If it was flesh /and smelled strongly，then /the ship was close to land．

Birds Sea birds could be used to show the way/ to land /when it was nowhere to be seen．In the evening

nesting birds return to land /and their nests．So /seamen could follow the birds /to land /even if they were offshore/ and in the open sea．

Using the weather

Fog Fog gathers at sea /as well as over streams /or rivers．Seamen used it /to help identify the position of a stream /or river /when they were close to land．

Winds Wise seamen used the winds/ to direct their sailing．They could accelerate the speed，but they could also be dangerous．So /the Vikings would observe the winds /before /and during their outward /or return journeys．

Using the sea Certain tides/ and currents could be used /by skillful sailors /to carry ships/ to their destination. These skills helped sailors/ explore the seas/ and discover new lands．They increased their ability/ to navigate new seas/ when they used instruments．

page 2: Using navigational instruments to help Finding longitude There was no secure method of measuring longitude /until the 17th century/ when the British solved this theoretical problem．Nobody knew that /the earth moved westwards/ 15 degrees/ every hour, but sailors did know an approximate method of calculating longitude /using speed /and time．An early method of measuring speed/ involved throwing a knotted rope/ tied to a log /over the side of the ship．The rope was tied to a log /which was then/ thrown into the sea．As the ship advanced through the water /the knots were counted/ as they passed through a seaman’s hands．The number of knots/ that were counted /during a fixed period of time/ gave the speed of the ship/ in nautical miles /per hour．Later, when seamen began to use the compass /in the 12th century /they could calculate longitude /using complicated mathematical tables．The compass has a special magnetic pointer /which always indicates the North Pole，so/ it is used to help find the

direction /that the ship needs to go．In this way /the ship could set a straight course /even in the middle of the ocean．

Finding latitude

The Bearing Circle It was the first instrument /to measure the sun's position．A seaman would measure the sun’s shadow/ and compare it /with the height of the sun/ at midday．Then/ he could tell if he was sailing on his correct/ rather than a random course. The Astrolabe The astrolabe, quadrant/ and sextant are all connected. They are developments /of one another．The earliest，the astrolabe，was a special all-in-one tool /for telling the position of the ship/ in relation to the sun/ and various stars /which covered the whole sky．This gave the seamen /the local time /and allowed them /to find their latitude/ at sea．However, it was awkward/ to use /as one of the points of reference/ was the moving ship itself．

The Quadrant This was a more precise/ and simplified version of the astrolabe．It measured how high stars were above the horizon /using a quarter circle/ rather than the full circle of the astrolabe．It was easier to handle /because it was more portable．Its shortcoming was that it still used the moving ship /as one of the fixed points of reference．As the ship rose /and plunged /in the waves，it was extremely difficult /to be accurate /with any reading．

The sextant The sextant was the updated version /of the astrolabe /and quadrant/ which reduced the tendency/ to make mistakes．It proved to be the most accurate /and reliable of these early navigational instruments．It works by measuring the angle /between two fixed objects /outside the ship/ using two mirrors．This made the calculations more precise /and easier to do．

III. Copying useful expressions and making sentences You are going to copy in your notebook all the useful expressions and make sentences of your own with them. sail the oceans, explore the oceans, plot a ship's position on a map, the voyages of travelers, before the 17th century,

at the mercy of…, have modern navigational aids, read these pages from an encyclopedia use nature to help, keep alongside the coastline, seem to have been…, the first and most useful form of exploration, carry the minimum amount of risk use celestial bodies, North Star, at the North Pole, at its highest position in the sky, at the equator, along the horizon, accomplished navigators, be able to use…to plot their positions, on a clear day, during the summer, use the sun overhead at midday to navigate by, use the height of the sun to work out their latitude, observe the clouds over islands, a special cloud formation, land close by use wildlife, see seaweed in the sea, tell…by the colour and smell, flesh and smelled strongly，close to land, use sea birds to show the way to land, in the evening, nesting birds, return to land and their nests, follow the birds to land, in the open sea ind latitude, the Bearing Circle, measure the sun's position, measure the sun’s shadow, compare…with…, the height of the sun at midday, sail on…, rather than a random course

a special all-in-one tool for telling the position of the ship, in relation to…, give sb the local time, find one’s latitude at sea, use as one of the points of reference, a more precise and simplified

version of the astrolabe, above the horizon, use a quarter circle, use the moving ship as one of the fixed points of reference, plunge in the waves，the updated version of the astrolabe and quadrant, reduce the tendency, make mistakes, the most accurate and reliable of these early navigational instruments, work by measuring the angle

IV. Transforming information Next you are going to read the text again to complete the chart below. SAILING THE OCEANS ■Using nature to help keeping alongside the ■Using navigational instruments to help

coastline ●Using celestial bodies: North Star; Sun; ●finding longitude

Clouds ●Using wildlife: Seaweed; Birds ●Using the weather: Fog; Winds ●Using the sea

●Finding latitude: The Bearing Circle; The Astrolabe; The Quadrant; The sextant

V. Closing down by reading more about sailing the oceans