Meaning of LINES in English

LINES

[plural] [noun] [C] UKa punishment for school students in which a sentence has to be written repeatedlyThe sentence that has to be copied out when a pupil is given some lines usually refers to the offence that has been committed.She got 200 lines for swearing at her teacher. Imagine having to write "I must not swear at my teachers" 200 times!

Cambridge English vocab.      Кембриджский английский словарь.