scalar variable

例句：

1. 1.In mathematics, a scalar variable is a number that can take on any real value.
   在数学中，标量变量是一个可以取任何实数值的数字。
2. 2. The scalar variable represents the intensity of the light source.
   标量变量代表了光源的强度。
3. 3. The scalar variable is used to represent the amount of money in a bank account.
   标量变量用于表示银行账户中的金额。