短暂性动词，延续性动词和现在完成时 延续性动词是指动作发生后还可以延续一段时间或者相当长的一段时间。如：live, work, study, learn, sleep等，延续性动词可以和表示一段的时间状语连用。 短暂性动词是指动作一旦发生就立即结束。它不能和一段时间连用。这类动词有：go, come, arrive, leave, begin, start, join, marry等； ★在否定句中，短暂性动词可以和表示一段时间的状语连用。 We haven’t heard from Jane for a long time. ★短暂性动词的肯定式不能与表示一段时间的for 或since 或how long 等状语连用。★值得注意的是，表示一段时间的状语除了“for+一段时间”外，还有since+n./从句（时间点），since+时间段+ago，疑问词how long，in the past+时间段，all these+时间段，from…to（时间点）以及till/until+n./句子等等。例如： .I have received his letter for three days（×） I have received his letter.（√） How long did she leave .（×） How long has she been away? (√) ★★★如果短暂性动词与表示一段时间的时间状语连用，必须将短暂性动词改为延续性动词。现归纳总结一下由非延续性动词到延续性动词的转换： arrive→be here ★除了用上面的转化形式之外，还可以用其他的表达形式： A. It is 或者 It has been+时间+since……（动词用过去式）， B.主语+谓语（过去时）+时间+ago。 例如： It’s five days since I received his letter. arrive→be here begin(start)→be on die →be dead come back→be back leave →be away (from) fall ill(asleep)→be ill( asleep) get up→be up go out →be out marry → be married finish →be over put on →wear 或be on open →be open close →be closed join →be in/ be a member of go to school→be a student borrow→keep buy/get→have dress → be dressed catch(a cold)→ have(a cold) get to know →know begin to study→study come to work→work move to → live in finish/end → be over come to → be in sit down → be seated His father died three years ago. 看一个句子可以用以下几种说法：他离开上海已经3 天了。 He left Shanghai three...
