【用方框中所给单词的适当形式填空,使短文正确,通顺,每词限一次（well,find,star,invent,ourany,have,one,direction,see）WhereareweThatwasabigquestionwhenwe（）exploredourworldlongago.Theearlyexplorers】

　　用方框中所给单词的适当形式填空,使短文正确,通顺,每词限一次

　　（well,find,star,invent,ourany,have,one,direction,see）

　　WhereareweThatwasabigquestionwhenwe（）exploredourworldlongago.Theearlyexplorersfoundthatthe（）intheskyweregoodlandmarks.Usingthestars,theycould（）outwheretheywereandinwhich（）theyweregoing.Thismethodworkedwellatnightaslongsdtheweatherwasgoodandthestarscouldbe（）.Butitdidnotworkso（）duringtherestofthetime.Thatwasaproblem.

　　Today,theproblem（）beensolvedbytheGlobalPositioningSystem.OrGPS.Itislikeaman-madestar.Wecanuseitat（）time,inanyplaceandinanyweathertofindout（）position.Itcanalsobeusedtostudytheshapeoftheearth.GPSisagreat（）thathelpsusexploreourplanetanddiscoverweare.