Peopleburncoal,gasandoiltogetenergy.Butthereareproblemswiththesefuels(燃料).(A)________,thesefuelscausepollution.Pollutionmakestheairandwaterunsafeforhumans.Secondly,thesefuelswillnotlastforever.Oneday,wewillrunoutofthesefuels.

Scientistsarelookingfornewkindsofenergy.OneisheatfromtheEarth.Weknowthat(B)地球中央非常热.WecannotreachthecenteroftheEarth,butinsomeplacetheheatfromtheEarth'scentercomestothesurfaceoftheEarth.Perhapsyouknowaboutsomeoftheseplaces.Oneplaceisvolcanoes(火山).Itisverydangeroustogonearanactivevolcano,(C)________wecannotusetheenergyfromthis.

AnotherkindofheatfromtheEarthishotsprings(温泉).Intheseplace,hotwatercomestothesurfaceoftheEarth.Ifthiswaterisnearatown,thehotwatercanbesentinpipes(管道)directlytopeople'shousestoheatthem.InIceland,thisisacommonwaytoheathouses.

(D)InAustralia,scientistsarelookingforwaystomakeenergyusinghotrocksunderthesurfaceoftheEarth.Theywanttopump(抽水)waterontothehotrocks.Whenthewaterhitstherocks,itmakessteam(蒸汽).Thesteamispipedtopowerstationswhere(E)itisusedtomakeelectricity.Theelectricitycanthenbesentalloverthecountry.

1.在文中(A)和(C)的空白处分别填入适当的单词。

　(A)____(C)____

2.将文中划线部分(B)译成英语。____

3.将文中划线部分(D)改写为：InAustralia,scientistsaretryingto____waystomakeenergy____hotrocksunderthesurfaceoftheEarth.

4.文中划线部分(E)指代的是____

5.从文中找出两个表示能源名称的词。____