加法:1、two+three=five

2、eight+two=ten

3、four+seven=eleven

4、two+five=seven

5、twelve+five=seventeen

6、nine+two=eleven

7、four+one=five

8、thirteen+six=nineteen

9、one+eight=nine

10、six+four=ten

减法1、four-one=three

2、six-two=four

3、twelve-two=ten

4、eight-three=five

5、ten-six=four

6、eighteen-nine=nine

7、nine-two=seven

8、sixteen-eight=eight

9、seven-four=three

10、five-one=four