| 1. | Students who cannot even do simple addition and subtraction
学生甚至不会做简单的加法和减法。 |
| 2. | Students who can not even do simple addition and subtraction
学生们甚至不能计算简单的加减法。 |
| 3. | Students who can not even do simple addition and subtraction
学生们甚至不能做简单的加减运算。 |
| 4. | Review on the research for addition and subtraction word problem solving
加减文字题解决研究概述 |
| 5. | Addition and subtraction calculation , simple and interesting game
加减法运算，简单而有趣的游戏。 |
| 6. | The first two basic operations in mathematics are addition and subtraction
数学中两个最基础的运算是加和减。 |
| 7. | Pressing return a couple more times will show an addition and subtraction
再按两次回车将显示加法和减法表达式： |
| 8. | Addition and subtraction
加法和减法（ |
| 9. | The danger : students who can not even do simple addition and subtraction
很危险的是，一些学生甚至连简单的加减法都不会做。 |
| 10. | He ' s only three , but he can already do simple problem in addition and subtraction
他只有3岁，但他已能做简单的加减法题目了。 |
