since有對比的意思嗎

沒有對比的意思，since意思是自從……時候，例如：

1、You've grown since the last time I saw you!自從我上次見到你後，你又見長了！

2、She's a changed woman since she got that job.她自從得到了那份工作，變得判若兩人。

3、I've lost six and a half pounds since I started my diet.從節食以來，我體重已減輕了六磅半。