【帮忙作一篇高中语法填空Theseahasalwaysinterestedman.Fromithecangetfood,minerals,andtreasure.Forthousandsofyears,hecouldsailonit.

　　帮忙作一篇高中语法填空

　　Theseahasalwaysinterestedman.Fromithecangetfood,minerals,andtreasure.Forthousandsofyears,hecouldsailonit._____(1)hecouldnotgofarbeneathitssurface.

　　Manwantstoexploredeepintothesea.However,hemustbreatheair,hecannotstayunderthewater'ssurfaceforany______(long)(2)oftime.Toexplorethedeepwater,manfacesevenmoredangersandproblems.

　　Adiver_____(3)wantstostayunderwaterformorethanafewminutesmustbreatheair_____(4)aspecialmixtureofgases.Hecanwearadivingsuitandhaveair_____(pump)(5)tohimfromabove.Orhecancarryatankofaironhisbackandbreathethroughahoseandamouthpiece.

　　Waterweighs800timesasmuchasair.____(push)(6)bytonsofwater,diver'sbodiesareundergreatpressure.

　　Whenadriverisundergreatpressure,hisbloodtakes____(7)someofthegaseshebreathes.Asherisestothesurface,thewaterpressurebecomes_____(8),ifthedriverrisestooquickly,thegasesinhisbloodfrombubbles.Thediveristhensuffering_____(9)thebends(潜水员病）.Thebendscancauseadivertodoubleupinpain.Theycan____(10)killhim.

　　尤其是第2,5,7,9题最好解释一下为什么