Since 引导的从句不论是延续性或非延续性动词, 都表示的是动作或状态的完成或结束.
注意一下句子翻译:
Since he lived in Nanjing, I have not heard from him. (= since he left Nanjing…)
自从他离开南京以来,我没有收到过他的信.
Since she was in Yangzhou, she has kept in touch with her former friends. ( since she left Yangzhou…)
她离开扬州以来,一直同过去的朋友保持着联系.
对比:
1). I have never seen him since he was ill.
他病好后,我就再也没有见到他.
2). I have never seen him since he fell ill.
他生病以后我就再也没有见过他.
It is / ( has been ) + 时间段 + since + 过去式
It is / has been two years since his father died.
= his father has been dead for two years. = his father died two years ago.
他的父亲去世两年了.
It has been 8 years since I graduated from university.
= I graduated from university 8 years ago.
It is 3 years since he smoked. 他三年不吸烟了.(即,从句动词延续性的,译成否定意义;从句动词非延续性的,译成肯定意义.)
It is 3 years since he left school.-----他毕业三年了.