Participate in BIGCS is completely voluntary.

参与出生队列研究是完全自愿的。

youdao

I said, their purpose is to let you know something on AIDS, completely voluntary.

我说，自己的目的是让大家对艾滋病有所认识，完全出于自愿。

youdao

Your participation in the Customer Experience Improvement Program is completely voluntary.

加入“客户体验改善计划”是完全自愿的。

youdao

The programs are completely voluntary, and even the most unhealthy can earn the same reward as the healthiest, so long as they work with a health coach.

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The new system would be completely voluntary.

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The program is also completely voluntary.

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