at some certain time

at some certain time at some certain time of his or her life 是什么意思 some time at times some certain kinks of at any time与at some time有什么区别? 求翻译简单英语句子：faiture at a certain period of time is acceptable. They want to do certain things at acertain time. 翻译谢谢 at some time in the past= At times,for a time,for some time,at a time,for the time in no time/at one time/at a time/in some time这些词都是什么意思? a certain time in the 翻译at a certain 急