1. 确定;有把握
    Certainty is the state of being definite or of having no doubts at all about something.

    e.g. I have told them with absolute certainty there'll be no change of policy...
           我已经十分肯定地告诉他们，政策不会变。
    e.g. There is too little certainty about the present state of the German economy.
           德国当前的经济非常不稳定。

2. 必然(性);肯定(性)
    Certainty is the fact that something is certain to happen.

    e.g. A general election became a certainty three weeks ago.
           3个星期前举行普选已确定无疑。
    e.g. ...the certainty of more violence and bloodshed...
           发生更多暴力和流血事件的必然性

3. 确定无疑的事情;必然的事
    Certainties are things that nobody has any doubts about.

    e.g. There are no certainties in modern Europe...
           当代欧洲没有什么是确定无疑的。
    e.g. The collapse of old certainties is reshaping the political parties.
           陈规旧矩的崩塌正在重塑各个政党。