1、延续性动词和短暂性动词转换归纳瞬间动词可以用于现在完成时，但不能和表示一段时间的状语连用如:for 和since 所引导的时间状语都表示一段时间.那就要将瞬间动词转化为表延续的动词或者表状态的be+名词形容词或副词介词短语等。 leave been away from buyhave borrowkeep diebe dead get upbe up put onbe on / wear come / get backbe back go to townbe in town losebe missing catch a coldhave a cold closebe closed / not 2、open open be open fall ill / asleep be ill / asleep begin /startbe on return-be back marry-be married finish-be over become-be come / go to be in / at arrive in （at）/ get to / reachbe in / at join + 名词-be in + 组织 / be a（an）+组织成员get /receive a letter fromhave a letter from 一看时间状语。如果句中没有表示过去确切时间的状语，常用3、现在完成时；如果有，则只能用一般过去时。如： I have visited the factory. I visited the factory last year.二看句首有无疑问词。如果笼统地问人家做过某事了吗（句首无疑问词），常用现在完成时；但进一步询问何时、何地、何原因、用什么方式做那事时（句首有疑问词）就要用一般过去时。如：Have you had your breakfast? Yes, I have.When did you have it? At seven thirty.注意： 这种用法是以连贯性问答为背景的。否则就需要具体情况具体分析。如： How many words have you learned by heart? How did you learn them by heart?三看句中谓语动词是否为延续性动词。如果表示的动作或状态一直延续到现在，最好选用延续性动词，并使用现在完成时；如果是瞬间动词，则用一般过去时。如： He has been a league member for}