70 Partn IWritinganEssal'
Transitions
between
ParagraphsA. Circlethetransitionexpressionsthatlinkparagraphsinthemodelessayon
pages58-59.
B. Connecttheideasinthefollowingparagraphsbyaddinga transitionword,
phrase,orclausetothetopicsentencesofthethird,fourth,andfifthpara-
graphs.Trytovarythetrall.sitionallinkingexpressionsyouuse.Youmay
rewritethetopicsentencesifnecessary.Thefirstonehasbeendoneforyouas
anexample.Icebergs:A PotentialSourceofWater
Incountrieswhererainfallis verysparse,lscientistsmustconstantlyseek
waystoincreasesuppliesofwater.Onemethodbeingconsideredistheuseof
desalinationplants,whichwouldremovesaltfromseawater.Anothermethod
beingconsideredis thetowingoficebergs.Accordingtothismethod,large
icebergsfromAntarcticawouldbewrappedinclothorplastic,tiedtopowerful
tugboatsbystrongropes,andtowedtothecountriesneedingfreshwater.While
thisplanmayhavesomepotential,therearecertainpracticalproblemsthatmust
besolved.
2 Thefirstproblem is theexpense.Accordingtoestimates,it would
costbetween$50millionand$100milliontotowa single
100-million-tonicebergfromAntarcticato,forexample,thecoastof
SaudiArabia.
3 is thepossibilitythattheicebergwouldmelt
enroute.^2 Nooneknowsifanicebergcouldbeeffectivelyinsulatedforsucha long
journey.Attheveryleast,thereisthepossibilitythatit wouldbreakupintosmaller
pieces,whichwouldcreatestillotherproblems.
4 thereis thedangerthata hugeblockofice
floatingoffanarid^3 coastcouldhaveunexpectedenvironmentaleffects.Theice
coulddrastically4changetheweatheralongthecoast, andit wouldprobably
affectthefishpopulation.
5 thecostofprovidingfreshwaterfrom
icebergswouldbelessthanthecostofprovidingwaterbydesalinization,
accordingtomostestimates.It wouldcostbetween 50 and 60 centspercubic
metertogetwaterfromaniceberg,asopposedtothe 80 centspercubicmeter
it wouldcosttogetthesameamountbydesalinization.
6 Inconclusion,beforeicebergscanbecomea sourceoffreshwaterinthe
future,problemsinvolvingcost,overallpracticality,andmostimportant,
environmentalimpact^5 mustbesolved.Isparse:smallinamount
2 enroute:duringthejourney(^3) arid:dry
4drastically:inanextremeway
5impact:effect
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