高中英语知识点总结：since从句的用法(共4页).docx

精选优质文档-倾情为你奉上高中英语知识点总结：since从句的用法1. Since从句为非延续性动词的过去时或现在完成时，时间的起点应该从从句动作完成时刻算起。例如：Things have changed a lot since I wrote to you last time.自我上次给你写信之后，情况已发生了很大的变化。She has lived with us since she has come here.自从她来到这里，就一直和我们住在一起。2. Since从句为延续性动词的一般过去时，表示动作或状态的结束。其含义与动词的词义恰好相反，具有否定意味。例如：All has changed since he was at home.自从他离开家以后，这里的一切都变了。I havent written to her since she lived in London.自从离开伦敦以来，我还没有给她写过信。He has