It is only achieved by education and mental discipline.

它只能通过“教育”和心智训练来实现。

The wake up call came early in my career when an opponent at the Italian open publicly questioned my mental discipline.

在我职业生涯的早期，一个对手在意大利公开赛上公开质疑我的精神纪律，这给我敲响了警钟。

In one experiment, they asked a group of students to improve their posture for two weeks, thereby practicing mental discipline in one area.

在一个实验中，他们要求一组学生改善两周他们的姿势，借此实践一个区域中的智力训练。

So when young people are critical of an over-tweeting president, they reveal a mental discipline in thinking skills — and in their choices on when to share on social media.

所以，年轻人批评总统过度使用推特时，揭示了他们在思维（以及选择什么时候在社交媒体上分享）上的自律。