Do you like math? 你喜欢数学吗？

　　You probably saw an equal sign in math. 你或许在数学中看到过等号。

　　The equal sign is a symbol in math. 等号是数学中的符号。

　　It is used to show that things are the same. 它用来表示事物是相同的。

　　When was the equal sign made? Who made it? 什么时候发明了等号？又是谁发明的？

　　It was invented by Robert Recorde in 1557. 1557年，罗伯特·雷科德发明了它。

　　How do you read "ten plus ten equals twenty"? 你怎么读“ten plus ten equals twenty”？

　　It is read as ten plus ten is equal to twenty. 它读作10加10等于20。