11-9
18-9
11-8
11-7
11-6
11-5
11-4
11-3
11-2
12-9
12-8
12-7
12-6
12-5
12-4
12-3
13-9
13-8
13-7
13-6
13-5
13-4
14-9
14-8
14-7
14-6
14-5
15-9
15-8
15-7
15-6
16-9
16-8
16-7
17-9
17-8
11-9
11-8
11-7
11-6
11-5
11-4
11-3
11-2
12-9
12-8
12-7
12-6
12-5
12-4
12-3
11
11
11
11
11
11
11
11
9
8
7
6
5
4
3
2
=2
=3
=4
=5
=6
=7
=8
=9
11-9
11-8
11-7
11-6
11-5
11-4
11-3
11-2
12-9
12-8
12-7
12-6
12-5
12-4
12-3
11
11
11
11
11
11
11
11
9
8
7
6
5
4
3
2
13-9
13-8
13-7
13-6
13-5
13-4
14-9
14-8
14-7
14-6
14-5
15-9
15-8
15-7
15-6
16-9
16-8
16-7
17-9
17-8
18-9
12
12
12
12
12
12
12
13
13
13
13
13
13
14
14
14
14
14
15
15
15
15
16
16
16
17
17
18
20以内退位减法表
9
8
7
6
5
4
3
9
8
7
6
5
4
9
8
7
6
5
9
8
7
6
9
8
7
9
8
9
竖着看
11-9
11-8
11-7
11-6
11-5
11-4
11-3
11-2
12-9
12-8
12-7
12-6
12-5
12-4
12-3
13-9
13-8
13-7
13-6
13-5
13-4
14-9
14-8
14-7
14-6
14-5
15-9
15-8
15-7
15-6
16-9
16-8
16-7
17-9
17-8
18-9
20以内退位减法表
横着看
11
12
13
14
15
16
17
18
9
9
9
9
9
9
9
9
11
12
13
14
15
16
17
8
8
8
8
8
8
8
7
7
7
7
7
7
6
6
6
6
6
11
12
13
14
15
16
11
12
13
14
15
11
12
13
14
11
12
13
11
12
11
5
5
5
5
4
4
4
3
3
2
11-9
11-8
11-7
11-6
11-5
11-4
11-3
11-2
12-9
12-8
12-7
12-6
12-5
12-4
12-3
13-9
13-8
13-7
13-6
13-5
13-4
14-9
14-8
14-7
14-6
14-5
15-9
15-8
15-7
15-6
16-9
16-8
16-7
17-9
17-8
18-9
20以内退位减法表
斜着看
18
17
16
15
14
13
12
11
9
8
7
6
5
4
3
2
17
16
15
14
13
12
11
9
8
7
6
5
4
3
16
15
14
13
12
11
9
8
7
6
5
4
15
14
13
12
11
9
8
7
6
5
11-9
11-8
11-7
11-6
11-5
11-4
11-3
11-2
12-9
12-8
12-7
12-6
12-5
12-4
12-3
13-9
13-8
13-7
13-6
13-5
13-4
14-9
14-8
14-7
14-6
14-5
15-9
15-8
15-7
15-6
16-9
16-8
16-7
17-9
17-8
18-9
20以内退位减法表
12-8
13-8
14-8
15-8
16-8
12-7
15-7
12-6
15-6
12-5
13-5
13-7
14-7
13-6
14-6
摘果子
12 - 3 = 9
13 - 8 = 5
13 - 6 = 7
11 - 8 = 3
15 - 7 = 8
11－3
8
13－5
15－7
12－4
14－6
16－8
17－9
2
3
4
5
6
7
口算比赛
作业：
观察第23页的20以内退位减法表，和我们整理的有什么不同？请你找出排列的规律。