Unit2SailingtheoceansPeriod1WarmingUp,Prereading&Reading同步精练(人教版选修9,课标通用)时间:45分钟Ⅰ
介、副词填空1.Thevoyagesoftravellersbeforethe17thcenturyshowthattheywerenot________themercy________theseaeventhoughtheydidnothavemodernnavigationalaids
2.Onacleardayespeciallyduringthesummerthesailorscouldusethesunoverhead________middaytonavigateby
3.Thereisaspecialcloudformationwhichindicatesthereislandclose________
4.Anearlymethodofmeasuringspeedinvolvedthrowingaknottedropetied________alogoverthesideoftheship
5.Thenumberofknotsthatwerecounted________afixedperiodoftimegavethespeedoftheshipinnauticalmilesperhour
6.________thiswaytheshipcouldsetastraightcourseeveninthemiddleoftheocean
7.________,itwasawkwardtouseasoneofthepointsofreferencewasthemovingshipitself
8.Astheshiproseandplungedinthewaves,itwas________diffic