动词完成时态练习.doc

动词的进行时态Step1 RevisionCheck up homework.Revise what was taught last time and ask some students to translate some sentences or answer some questions.Step2 Unfolding延续性动词一、延续性动词和非延续性动词的概念英语中，动词按其动作发生的方式、动作发生过程的长短，可分为延续性动词和非延续性动词。延续性动词表示能够延续的动作，这种动作可以延续下去或产生持久影响。如：learn, work, stand, lie, know, walk, keep, have, wait, watch, sing, read, sleep, live, stay等。非延续性动词也称终止性动词、瞬间动词或短暂性动词，表示不能延续的动作，这种动作发生后立即结束。如：open, close, finish, begin, come, go, arrive, reach, get to, leave, move, borrow, buy等。二、延续性动词的用法特征1. 延续性动词可以用于现在完成时，其完成时态可与表示“时间段”的状语连用。表示时间段的短语有：for+一段时间（eg: for two years）, since从句（eg: since he came here）, since+时间点名词（eg: since last year）, during the past three years, how long, for a long time等。例：I have learned English since I came here. 自从我来到这儿就学习英语了。2. 延续性动词不能与表示短暂时间的“时间点”状语连用。如：It raind at eight yesterday morning.（误）rain为延续性动词，而at eight表示“时间点”，前后显然矛盾。如果要用延续性动词表示一瞬间的动作，可以借助come, begin, get等非延续性动词来表示。上句可改为：It began to rain at eight yesterday morning.又如以下这段对话：-When did you get to know Jack? 你什么时候认识Jack的？-Two years ago. 两年前。-Then youve known each other for more than two years. 也就是说你们俩认识两年多了。-Thats right. 没错。非延续性动词 1. 非延续性动词可用来表示某一动作完成，因此可用于现在完成时。如：The train has arrived. 火车到了。Have you joined the computer group? 你加入电脑小组了吗？2. 非延续性动词表示的动作极其短暂，不能持续。因此，不可与表示一段时间的状语连用（只限肯定句）。如：(1) 他死了三年了。误：He has died for three years.正：He has been dead for three years.正：He died three years ago.正：It is three years since he died.正：Three years has passed since he died.(2) 他来这儿五天了。误：He has come here for five days.正：He has been here for five days.正：He came here five days ago.正：It is five days since he came here.正：Five days has passed since he came here.(1)、(2)句中的die、come为非延续性动词，不能与表示“时间段”的状语连用。那么，应如何正确表达呢？可以采用下面的四种方法：a. 将句中非延续性动词转换为相应的延续性动词，如上面两例中的第一种正确表达方式。下面列举几例：leave→be away,borrow→keep,buy→have,begin/start→be on,die→be dead,move to→live in,finish→be over,join→be in/be a member of, open sth.→keep sth. open,fall ill→be ill,get up→be up,catch a cold→have a cold。b. 将句中表示“时间段”的状语改为表示过去