The English word arbitration, starting with a, is an Arbitrary symbol in reverse, meaning "for any given" or "for all".

The English word Exist, starting with e, is a symbol of existence in turn.

Example: "For any given ε >; 0 "written" ε& gt； 0 ","There is a positive integer n "? Positive integer n "

These two symbols mainly exist in the expressions of calculus, and the examples I gave are also from textbooks:)

A simpler example-"The straight line distance between two points is the shortest": Two o'clock? The shortest path, and the path is a straight line "Hehe, please forgive me for the poor translation. It's good to understand the meaning.