a line in education的用法和样例：
- Those who never blot a line in writing are rare.
- Rocko has never fired a line in his life.
- Students are standing in a line，in fours.
- The cars are running in a line in the street.
- An attempt by the computer or by a station to gain control of a line in order to transmit data.
- This was just a line in his charade he couldn't sacrifice.