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单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,*,*,*,十几减九的退位减法,青岛版,一年级下册,一 逛公园20以内的退位减法,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,从图中,你发现了哪些数学信息?,一共来了,15,人,有,9,个女生,一共有,17,个气球,卖了,9,个,根据这些信息,你能提出哪些问题?,有几个男生?,还剩几个气球?,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,有几个男生?,15 9=(,个,),6,已知:一共来了,15,人,有,9,个女生。,数数,14,、,13,、,12,、,11,、,10,、,9,、,8,、,7,、,6,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,15 9=(,个,),9,6,15,15,9,6,6,想加算减,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,先拿走,5,个,再拿走,4,个,15,5,10,10,4,6,连 减,15 9=(,个,),6,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,10,9,1,1,5,6,破 十,15 9=(,个,),6,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,还剩几个气球?,(,个,),17,7,10,10,2,8,17,-,9,8,已知:一共有,17,个气球,卖了,9,个。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,1.,16 9=,13 9=,7,4,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,2.,12,-,9,3,11,-,9,2,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,3.,(,个,),(,支,),17,-,9,8,18,-,9,9,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,4.,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,十几减,8,、,7,的退位减法,青岛版,一年级下册,一 逛公园20以内的退位减法,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,1,、还剩几只船?,2,、还剩几瓶矿泉水,?,你能提出什么数学问题?,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,还剩几只船?,15,8=(,只,),15,可以分成,10,和,5,10-8=2,2+5=7,7,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,还剩几只船?,15,8=(,只,),8,可以分成,5,和,3,15-5=10,10-3=7,7,15-8=7,8+7=15,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,11,8=17,8=,14,8=12,8=,试一试,3,9,6,4,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,还剩几瓶矿泉水?,=(,瓶,),16,7,16,可以分成,10,和,6,10,7,3,3,6,9,7,可以分成,6,和,1,16,6,10,10-1,9,16,7,9,7+9,16,9,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,12,7=15,7=,14,7=13,7=,试一试,5,8,7,6,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,1.,算一算,8,4=8,6=7,4=7,7=,12,8=14,8=11,7=14,7=,12,4,14,6,11,4,14,7,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,12,7,5,17,8,9,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,3.,8,7,15,8,7,15,8,7,15,7,9,16,7,9,16,7,9,16,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,十几减,6,、,5,、,4,、,3,、,2,的退位减法,青岛版,一年级下册,一 逛公园20以内的退位减法,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,你能提出什么数学问题?,1,、小亮还剩几条鱼?,2,、,小新还剩几条鱼,?,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,小亮还剩几条鱼?,14,6=(,条,),6+8=14,14-6=8,10-6=4,4+4=8,8,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,试一试,12-6=,11-6,=,15-6,=,13-6,=,5,9,7,6,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,小新还剩几条鱼?,=(,条,),12,-,3,3+9=12,12-3=9,10-3=7,2+7=9,9,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,试一试,11-4=,12-5,=,11-2,=,7,9,7,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,12,-,4,8,11,-,3,8,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,7,6,5,4,7,6,5,4,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,6,+,5,11,11,-,6,5,11,-,6,5,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,3,9,14,9,9,6,9,9,17,7,2,14,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,二 下雨了,认识钟表,青岛版一年级下册,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,你还能提出什么问题,?,小力是什么时间到家的?,小云是什么时间到家的?,小青和小林分别是什么时间到家的?,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,仔细观察:钟面上有什么?,分针,时针,1,2,1,2,3,11,1,0,4,5,7,6,8,9,数字,钟面上长的是时针,短的是分针。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,小力,你是什么时间到家的?,钟面上时针指着,5,,分针指着,12,。,是,5,时。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,你能说出钟面上表示的是几时吗?你是怎样知道的?,3,时,7,时,10,时,分针指着,12,,时针指着几,就是几时。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,小云是什么时间到家的?,时针指在,5,和,6,之间,分针指着,6,。,是,5,时半。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,你能说出钟面上表示的是几时吗?你是怎样知道的?,1,时半,7,时半,10,时半,分针指着,6,,时针指着几,就是几时半。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,小青和小林分别是什么时间到家的?,小林刚过,5,时到家。,小青快到,5,时到家。,快到,5,时和刚过,5,时都可以说大约,5,时。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,8,1,2,11,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,2,3,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,5,6,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,认识,100,以内的数,青岛版一年级下册,三 丰收了,100,以内数的认识,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,你能提出什么问题?,玉米有多少个?,辣椒有多少个?,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,100,以内数的大小比较,青岛版一年级下册,三 丰收了,100,以内数的认识,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,你能提出什么问题?,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,小玉和小玲谁摘的多?,只要比一比,42,和,27,谁大就可以了。,27,42,42,在,27,的后面,,42,大。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,小玉和小玲谁摘的多?,我先比较十位上的数。,42,27,4,2,40,比,20,大,所以,42,比,27,大。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,试一试,在 里填,里“,”,、,“,”,、,“,”“或,“,=,”。,7,4,9,9,5,5,4,4,2,8,1,0,十位上的数,相同,,怎样比较两个数的大小?,个位上数大的那个数就大。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,32,23,100,89,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,3.,29,35,42,64,67,70,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,4.,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,有关整十数的加减法,青岛版一年级下册,三 丰收了,100,以内数的认识,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,你能提出什么问题?,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,爸爸和妈妈一共摘了多少个?,40+30=,(个),我数一数,4,个十加,3,个十得,7,个十,是,70,。,70,50,、,70,。,60,、,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,试一试,10+50=,60+30=,90-70,=,80-20=,60,90,20,60,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,妈妈和小阳一共摘了多少个?,=,(个),30,6,36,3,个十,6,个一,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,你会计算,56-50,和,23-3,吗?,56-50,=,6,百,十,个,56,里面有,5,个十,和,6,个一,。,减去,5,个,十,,6,个一是,6,。,还,剩,6,个一,。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,23-3=,20,23,里面有,2,个十,和,3,个一,。,减去,3,个一,,2,个十是,20,。,还剩,2,个十,。,百,十,个,你会计算,56-50,和,23-3,吗?,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,20,+,30,50,70,-,40,30,20,+,3,23,46,-,6,40,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,2.,20,7,20,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,综合与实践:智慧广场,青岛版一年级下册,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,一边数一边写。,从,1,写到,100,,一共要写多少个,9,?,9,19,2989,90,9199,一共写了20,个,“9”,。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,用百数表,找一找。,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,一共写了20,个,“9”,。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,9,1,9,2,9,3,9,5,9,4,9,6,9,7,9,8,9,9,9,个位是“,9,”的数:,个位上,一共,有,10,个,“9”,。,十位是“,9,”的数:,9,0,9,1,9,2,9,3,9,4,9,5,9,6,9,7,9,8,十位上一共有,10,个,“9”,。,9,9,还可以这样想:,一共写了20,个,“9”,。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,先按顺序写出个位是“,9,”的数,再写出十位是“,9,”的数,然后数一数一共写了多少个“,9,”。,有顺序的列举才能保证不遗漏,不重复。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,一共写了20,个,“8”,。,一共写了20,个,“7”,。,一共写了20,个,“6”,。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,0,9,9,1,8,9,2,7,9,3,6,9,4,5,9,5,4,9,6,3,9,7,2,9,8,1,9,9,0,9,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,玉米有多少个?,我们来数一数。,一共有,28,个。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,玉米有多少个?,我们来摆一摆。,2,个十,8,个一,一共有,28,个。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,玉米有多少个?,我们来拨一拨。,一共有,28,个。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,在计数器上从,28,拨到,31,2,8,9,3 0,3 1,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,辣椒有多少个?,1,、,2,、,399,如果再加,1,个是多少呢?,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,可以用学具来数一数。,10,个十,是,100,。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,1,0,0,从右边起,第一位是个位,第二位是十位,第三位是,百位,。,可以在计数器上摆一摆。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,1.,4,1,41,3,9,39,8,2,82,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,2.,23,36,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,3.,60,100,44,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,青岛版一年级下册,两位数加一位数(不进位)、两位数加整十数,五 绿色行动,100,以内的加减法(一),Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,我浇了,26,棵,我浇了,26,棵,我浇了,30,棵,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,想,从图中,你知道了哪些数学信息?,东东浇了,3,棵。,芳芳浇了,30,棵。,亮亮浇了,26,棵。,根据这些信息,你能提出什么问题?,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,亮亮和东东一共浇了多少棵花?,26+3=,(棵),27,、,28,、,29,我来摆一摆,拔一拔,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,6,3,9,20,9,29,26+3=,(棵),为什么要先算,6,3,呢?,想,29,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,百,十,个,26+3=,(棵),29,6,3,9,20,9,29,为什么要把这,3,个珠子拨在个位上?,想,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,百,十,个,20+9=29,6+3=9,在小棒图中是指哪一部分?,在计数器图中又是指哪一部分?,在小棒图中是指哪一部分?,在计数器图中又是指哪一部分?,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,试,一,试,42,+,3,=,44,+,4=,31+8,=,5+33,=,6+23,=,54+2,=,4,5,3,8,5,6,4,8,3,9,29,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,亮亮和芳芳一共浇了多少棵花?,26+30=,(棵),为什么要先算,20,30,呢?,20+30=50,50+6=56,想,59,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,百,十,个,26+30=,(棵),20+30=50,50+6=56,为什么要把这,3,个珠子拨在十位上?,想,59,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,百,十,个,20+30=50,50+6=56,在小棒图中是指哪一部分?,在计数器图中又是指哪一部分?,在小棒图中是指哪一部分?,在计数器图中又是指哪一部分?,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,3,5+20=,22+,70=,31+3,0=,4,0+2,3,=,6,0,+27,=,54+,10=,5,5,63,64,92,61,8,7,试,一,试,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,2 6+3 0=5 6,2 6+3=2 9,讨,论,
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