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rapid(快速的）populationgrowth（增长）6hundredmillionhowtosolve(解决)theproblemcontrolthebirthrate(出生率)Kenya(肯尼亚）inAfrica（非洲）thepopulationwillincrease（增长）10timesinthenext80years1,3billion（十亿）UsedtoliveinthecountryMorethan65%liveincities.Theproblemofovercrowding(过度拥挤)InAsiaisfacedwithagingproblem老化Whatcauses(引起)it?thepopulationisdoubl(e)ing(增加一倍)every24yearsInEurope(欧洲)Theyoungcouplehave1childornone.Onaverage,menlivetobe76,women,78.平均futureproblemsBytheyear2200,theworldpopulationwillbeabout10billion.rapidpopulationgrowthcauses(引起)waterpollutionairpollutionnoisepollutionthrowaway(扔掉)millionsoftonsofrubbishpollutetheenvironment污染berecycled(被回收利用)plasticchemicalTherefore,wemuststopusing…coalbeusedupsomedayCan’tbealwaysavailable(可获得的)naturalresourcesproblemTherefore,wemustsaveandprotect…