这些名词均含有“确信无疑”之意。
certainty : 指在客观上和主观上都无一丝一毫的怀疑。
- There are few absolute certainties in life.
世事无绝对。 - political/moral certainties
政治上 / 道德上确定无疑的事 - Her return to the team now seems a certainty.
她的归队现在似乎已成定局。
assurance : 侧重依靠个人力量、本能、方法或对其他人或事的完全信任，强调有信心。
- She gave me her assurance (that) she would sign the contract immediately.
她向我保证她会马上签署合同。 - Despite the government's repeated assurances to the contrary, taxation has risen over the past decade.
尽管政府一再保证不会增税，可在过去10年中税收还是提高了。
conviction : 多指在理性基础上清除了原有的疑虑或无把握，着重对证据的主观反应。
- He said he was enjoying his new job, but his voice lacked conviction.
他说他喜欢自己的新工作，但口气不怎么坚定。 - He said he agreed but his voice lacked conviction.
他说他赞同，但语气不坚定。 - The leader's speech in defence of the policy didn't carry much conviction.
那位领导人为政策辩护的讲话不是很有说服力。
