I mean, there are some cautious steps I can take, but ultimately I cannot guarantee myself that.

我的意思是，我可以采取一些谨慎的措施，但最终，我不能保证自己（不会患病）。

youdao

I am sorry, I cannot guarantee, but I will do my best.

对不起，我不能保证，但是我会尽最大努力。

youdao

Alex is the captain, the symbol of the club and may not be too happy with my technical choices, but I have four strikers of the highest level and I cannot guarantee a place for everyone.

阿莱是队长、是球队的象征，也许不会对我的选择感到高兴，但是我有四个世界级的前锋，我不能为每一个都保证位置。

youdao

Hopefully within two years, probably not next year, but within two years, there will be positive psychology class offered, but I certainly cannot guarantee it.

但愿两年内，明年可能性不大，但是两年内，学校会再次开设积极心理学课程，但我无法保证。

哈佛公开课 - 幸福课课程节选