| 1. | He introduced a notation for negative numbers .
他为负数引进了一个符号。 |
| 2. | This delay notation has been adopted .
已经采用了这种延时符号。 |
| 3. | A variety of different symbols is in use .
符号的用法不统一。 |
| 4. | A concept may be represented by many symbols .
许多个符号可以代表一个概念。 |
| 5. | White marks painted on the trees show the route .
涂在树上的白色符号显示出路线。 |
| 6. | K is the symbol used for the kelvin units of temperature .
K为开氏温度单位符号。 |
| 7. | Language is a system of signs that express ideas .
语音是一种表达观念的符号系统。 |
| 8. | Please make sense of these marks on paper immediately .
请马上弄清这些符号的意义。 |
| 9. | The suggestive notation has been chosen purposely .
这个有启发性的符号是特意选择的。 |
| 10. | This operation is called inversion and is symbolized i .
这个操作叫倒反，用符号i表示。 |
