現(xiàn)在完成時(shí) 構(gòu)成：主語(yǔ)+助動(dòng)詞have, has+過(guò)去分詞

和你一起學(xué)習(xí) 現(xiàn)在完成時(shí)用法：
1） 表示過(guò)去發(fā)生的和現(xiàn)在有某種聯(lián)系的動(dòng)作，常和just, usually, already, since等時(shí)間副詞連用。
　　i have just had lunch. （飽了，不用再吃了。）
　　he has had a cup of tea.（不渴了，不用再喝。）
　　they have already had their holiday. （不能再度假了。）
　　the boy has already read the book. （已經(jīng)知道書(shū)的內(nèi)容了，不用再看了。）

2） 詢問(wèn)別人是否做過(guò)某事一般用現(xiàn)在完成時(shí)：
　　have you finished your homework?
　　have you been to beijing?
　　have he seen the film?

3） 表示開(kāi)始于過(guò)去并持續(xù)到現(xiàn)在的動(dòng)作
　　i have lived in beijing for twenty years.
　　i have worked for this school for 1 year.
4） 表示一種經(jīng)歷，經(jīng)驗(yàn)：去過(guò)…地方，做過(guò)…事情，經(jīng)歷過(guò)…事情
　　i have never had a bath.
　　i have never seen a film.
　　i have never been to cinema.
　　i have ever been to paris.
　　have been to表示去過(guò)，have gone to 表示去了
　　i have been to london.（人已經(jīng)回來(lái)）
　　he has gone to london.（人還在那里）

5） 表示一種結(jié)果， 一般不和時(shí)間副詞聯(lián)用
　　i have lost my pen.
　　i have hurt myself.
　　he has become a teacher.
　　she has broken my heart.

句型變化：
★變疑問(wèn)句將助動(dòng)詞移到句首，變否定句在助動(dòng)詞后面加not.
　　have you lost your pen? i have not lost my pen.

★肯定回答及否定回答
　　yes, i have. / no, i have not.

★特殊疑問(wèn)句
　　what have you done?
　　what has he done?

一般過(guò)去時(shí)與現(xiàn)在完成時(shí)的區(qū)別：
　　凡是有明確的表示過(guò)去的時(shí)間狀語(yǔ)的句子為過(guò)去時(shí)。
　　注意：有些動(dòng)詞表示的動(dòng)作有一個(gè)終點(diǎn)，不能再延續(xù)，因此不能和表示一段時(shí)間狀語(yǔ)連用。
　　錯(cuò)：i’ve left beijing for 3 days.
　　對(duì)：i left beijing 3 days ago. i have been away from being for 3 days.