湖北省松滋市第二中学高三英语选修九《Unit 2 Sailing the oceans》学案PART one: 篇章理解 Page one& two:Fast-reading Nature<4> Question:What did people use to help sailing? Instruments<6>Page one:→→Using nature: to help keep alongside the coastline North star:________________→→Using celestial bodies: Sun:________________ Clouds:________________ If seaweed was fresh and smelled strongly, the ship ___________.→→Using wildlife Sea birds could be used ________________ when it was nowhere to be seen. Fog:________________________ of a stream or river→→Using the weather Winds:__________________________Page two:Using navigational instruments1. to find longitude :the compass ________________ ________________2. to find latitude ________________ the sextant (六分仪) 3.What is the use of a bearing circle, astrolabe, quadrant or sextant? →→to ________________ 4.What is the use of a compass? →→to ________________5.the working principles of the following instruments: Bearing circle:to compare the height of the sun at the moment with the position of the sun at midday Astrolabe: 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 Quadrant: a more precise form of the astrolabe to measure how high stars are above the horizon and compare that measurement with previous measurements Sextant:an updated version of the quadrant which was more accurate to measure 1the angle between tow fixed pints outside the shipPART one: 知识点整理大考点１ mercy<1> Ask /beg for mercyShow mercy to sb=have mercy on sbAt the mercy of ＝under the control of sb =in the power of sb.<2>It is mercy that......
