by the time 与before 有何分别?

by the time 与before 有何分别? a cecond time与 the second time有何区别 by the time与by的区别 at the age of 与by the time of 与at that time后面分别加什么时态? time pass by 与 time go by 有什么区别? when与by the time的区别 "the time before by the time,at the time,in the time 分别什么意思?怎样区分? 用by the time和before造两个完成时的句子 since/by/before the time he was worked as a translator. before与after有何区别?该如何区分? by the time ,by then