They were completely unable to maintain discipline.

她们完全不能维持纪律。

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We need to find more creative ways to discipline our students and to maintain control in the classroom.

我们需要用更有创意的方法约束学生，维持课堂纪律。

反对体罚 - SpeakingMax英语口语达人

They had proved unpopular with head teachers, who protested they undermined efforts to maintain discipline in schools.

BBC: Expulsions rise for second year

It also means that we're working with teachers to determine, what's the best way to discipline -- maintain discipline in a classroom?

WHITEHOUSE: Online Town Hall

Retirement investors, on the other hand, need very simple counsel: Save more, invest in a diversified way, defer taxes and maintain discipline.

FORBES: Are You Addicted to High Fund Fees?