两位数减一位数退位减法练习17-8=27-8=37-8=64-6=54-6=44-6=34-6=24-6=14-6=25-6=14-9=33-7=46-9=22-4=23-8=12-6=52-9=42-8=32-4=75-7=62-5=46-8=28-9=16-8=21-4=18-9=35-6=31-4=16-7=33-5=32-5=42-5=57-9=61-4=73-5=74-6=54-7=23-4=36-8=14-5=16-8=23-6=26-8=14-7=82-6=84-7=91-4=67-9=55-6=47-8=11-4=21-4=31-4=41-4=51-4=14-7=24-7=34-7=1
