The trainer simulates a variety of maintenance situations and provides realistic feedback to students' actions.

教练机模拟各种维护状态，并对学员的行为提供现实的反馈。

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Certainly, the smaller the better, to allow for more interaction with and feedback from the trainer.

当然越少越好，这样能允许有更多的互动和来自老师的信息反馈。

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Much like having a personal trainer on hand, real-time feedback helps the user to know when they have successfully shifted the heart rhythms and the emotions.

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But this isn't encouraged as it's harder for the trainer to see two people at once and to give feedback.

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