第 74 课: 数学运算-1

This is an addition problem. 这是加法。

This is a subtraction problem. 这是减法。

This is a multiplication problem. 这是乘法。

This is a division problem. 这是除法。

When these numbers are added, their sum equals 10. 当这些数加起来时，它们的和等于十。

When these numbers are added, their sum is greater than 10. 当这些数加起来时，它们的和大于十。

When these numbers are added, their sum is less than 10. 当这些数加起来时，它们的和小于十。

When these values are added, we don't know how much their sum is. 当这些数加起来时， 我们不知道它们的和是多少。