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1、20以内的退位减法,复习：,9+2= 8+6= 7+4= 6+5= 5+9= 4+7= 8+5= 7+5= 8+3= 9+5= 7+8= 5+7=,11,14,11,11,14,11,13,12,11,14,15,12,9+6=,9+7=,9+3=,15,16,12,9+8=,17,9+4=,13,9+5=,14,9+2=,11,9+（ ）=12,3,5,摆一摆，算一算。,10-9=1；1+( )=( )。,9+( )=12； 12-9=( )。,3,你喜欢哪种方法？ 还可以怎样计算？,3,3,2,3,做一做,128=4（个）,114=7（只）,计算,12-5= 11+0= 12-3= 14+
2、4= 10-6= 11-5= 10-4= 13-7= 6+9= 13-9= 11-9= 12-0=,7,11,9,18,4,6,6,6,15,4,2,12,跳木桩,=,给、或=找个家 。 12-9 4 11-9 11+9 13-3 13-9 18- 9 9,139,8,3,7,5,2,4,6,159,149,189,179,129,119,169,139,8,3,7,5,2,4,6,159,149,189,179,129,119,169,139,8,3,7,5,2,4,6,159,149,189,179,129,119,169,8,3,7,5,2,4,6,159,149,189,179,129
3、,119,169,139,8,3,7,5,2,4,6,159,149,189,179,129,119,169,139,8,3,7,5,2,4,6,159,149,189,179,129,119,169,139,8,3,7,5,2,4,6,159,149,189,179,129,119,169,139,8,3,7,5,2,4,6,159,149,189,179,129,119,169,139,8,3,7,5,2,4,6,159,149,189,179,129,119,169,139,8,3,7,5,2,4,6,159,149,179,129,119,169,139,189,13-9,14-9,15-9,胜利,19-9,17-9,12-9,11-9,18-9,20-9,（ ）-9=5,16-9,入口,树上原来有14只小鸟，,飞走了9只小鸟。,原来有1个松果，小松鼠搬走了9 个。,14-9=5（只）,15-9=6（个）,11 9 = 2,12 9 = 3,13 9 = 4,14 9 = 5,15 9 = 6,16 9 = 7,17 9 = 8,18 9 = 9,11 9 = 2 12 9 = 3 13 9 = 4 14 9 = 5 15 9 = 6 16 9 = 7 17 9 = 8 18 9 = 9,
