persistence perseverance consistence之间字义有何不同？

hy2007

就我的理解
persistence: 是指对一件事或某个观念的坚持
而perseverance：意指坚忍不拔 而我的解读是为了完成某件事
能够坚持忍耐完成它
而consistence： 是指对某件事 观念或行为有一致性
请问这3者之间有何不同 尤其在形容一个人的行为或价值观的用法上
还是他们可算同义字？

csudeng

persistence :
1 the fact of continuing to try to do sth despite difficulties, especially when other people are against you and think that you are being annoying or unreasonable:

The old man's persistence annoyed me.
那个老人的固执使我恼火。
2.the state of continuing to exist for a long period of time:

The persistence of the heavy rain hampered the flow of traffic.
持续的大雨阻碍了交通运行。

csudeng

perseverance :
(approving) the quality of continuing to try to achieve a particular aim despite difficulties:

By perseverance the crippled boy learned how to swim.
那个跛足的男孩通过不屈不挠的努力学会了游泳。

csudeng

consistence = consistency

(approving) the quality of always behaving in the same way or of having the same opinions, standard, etc.

Your behavior lacks consistency -- you say one thing and do another!
你的行为缺乏一致性--说的是一回事,做的却是另一回事!