Written warnings are even more effective.

书面警告会更有效。

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Written warnings followed by training, re-training or counseling sessions will be given to employees who make minor and undesirable offenses.

对于员工违反公司纪律情节轻微者，将发给书面警告，并给予对应之教育训练、再训练或咨询。

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Three Metropolitan Police officers have been given written warnings over the "unprofessional and insensitive manner" in which they handled two rape reports.

BBC: Three Met officers warned over handling of rape cases

Court action could be taken against individuals who ignore written warnings and 'technical measures' including disconnecting someone from the web could also follow.

BBC: BT ordered to block links to Newzbin 2 website

Symbols indicating content suitable for over-15s or 18s have recently been doubled in size, and the gaming industry decided voluntarily to introduce written warnings of adult content on the game box.

BBC: Campaigners say school bullies leave long-lasting scars