0 to choose not to be part of an activity or to stop being involved in it -- 选择不参与；选择退出
1 a situation in which some members of a group choose not to join or be involved in an activity -- 主动选择退出
Since the opt-out, the hospital has been responsible for its own budgeting. 自从主动选择退出后，这家医院要对自己的预算负责。
Allowing richer individuals to opt-out of contributions to public insurance is likely to decrease the progressivity of a given financing system.
Sometimes, it is important to recognize that the flexibility of opt-out provisions is limited by what is technologically feasible.
In some countries, however, employees are given the option to opt-out to another pension benefit provider at the time engagement.
One alternative is automatic enrollment in personal accounts with a voluntary opt-out provision.
Currently, many opt-out procedures administered by web sites and others are hopeless and cumbersome, making it nearly impossible for citizens to exert real control.
Persons who do not want samples of their tissue to be used for research will have to notify the opt-out register.
Allowing richer individuals to 'opt-out' of contributions to public insurance is likely to decrease the progressivity of a given financing system.
Other countries continue this pattern of differences between opt-out and opt-in systems.
