A generalization of arithmetic in which symbols, usually letters of the alphabet, represent numbers or members of a specified set of numbers and are related by operations that hold for all numbers in the set.
代数学计算的普遍原理, 其中通常为字母表中字母的符号, 其代表数字或一组特定数字中的几个数字, 它们通过对组中全部数字都适合的运算法则相联系
A string of one or more characters used to separate or organize elements of computer programs or data; for example, parentheses, blank character, arithmetic operator, if, "BEGIN" .
用来分隔或组织计算机程序元素或数据元素的字符或字符串。例如括号、空格符、算术运算符、if（如果）、“BEGIN＂等。
I'm good at history but not so hot at arithmetic.
我的历史成绩不错, 但算术不太好.
