as, because, for, since

1. She moved to London last May and has since got a job on a newspaper.
   她去年五月到倫敦，此後一直在報社工作。
2. It was the first time I'd won since I'd learnt to play chess.
   自從我學會下國際象棋以來，這是我第一次贏。
3. How long is it since we visited your mother?
   自從我們看望你母親以來到現在有多長時間了？
4. We've been friends ever since we met at school.
   自從我們在學校認識之后，我們就一直是好朋友。
5. Since you can't answer the question, perhaps we'd better ask someone else.
   既然你無法回答這個問題，我們最好再問問別人。