很多同學(xué)在剛學(xué)習(xí)現(xiàn)在完成時(shí)時(shí)，都覺得很茫然，因?yàn)樗坪跖c一般過去時(shí)相似。那是因?yàn)檫@兩種時(shí)態(tài)描述的動(dòng)作都開始于過去。其實(shí)不然，現(xiàn)在完成時(shí)主要表示，發(fā)生在過去的動(dòng)作延續(xù)到現(xiàn)在剛剛完成、或許還要延續(xù);側(cè)重于這個(gè)動(dòng)作對現(xiàn)在帶來的結(jié)果、產(chǎn)生的影響、積累的總和等等。而一般過去時(shí)則只不過是表示動(dòng)作發(fā)生在過去的什么時(shí)候。弄清了這一區(qū)別，就很容易理解現(xiàn)在完成時(shí)了。
現(xiàn)在完成時(shí)
定義
現(xiàn)在完成時(shí)是過去的動(dòng)作或狀態(tài)持續(xù)到現(xiàn)在并且已經(jīng)完成，對現(xiàn)在造成的影響，可能持續(xù)發(fā)生下去。在英語時(shí)態(tài)中，“時(shí)“指 動(dòng)作 發(fā)生的時(shí)間，”態(tài)“指動(dòng)作的樣子和 狀態(tài) 。
1.表示到說話人說話時(shí)已經(jīng)完成的動(dòng)作，卻對現(xiàn)在仍有影響或結(jié)果。例如：He has lost his book.他丟了他的書。2.表示事情開始與過去，卻一直持續(xù)到現(xiàn)在還在進(jìn)行的事情。例如：He has taught in our school for 30 years.他在我們學(xué)校教書已有30年了。3.表示從過去某個(gè)時(shí)間直到現(xiàn)在的這個(gè)時(shí)間范圍內(nèi)不斷重復(fù)發(fā)生的動(dòng)作或情況，并且這個(gè)不斷重復(fù)的動(dòng)作有可能繼續(xù)下去，也有可能到現(xiàn)在就結(jié)束。例如：My father has always gone to work by bike.我父親一向騎車上班。4.同一般現(xiàn)在時(shí)可以表示將來一樣，現(xiàn)在完成時(shí)也可以在時(shí)間狀語從句里表示將來。例如：I’ll wait until he has written his letter.我愿等到他把信寫完。
構(gòu)成
主語 + have / has + done(過去分詞) + …
句型
肯定句: ① 主語 + have / has + done + …She has been to Shanghai.她去過上海.I have finished doing my homework.我已經(jīng)完成我的作業(yè)了.
否定句: ① 主語 + have / has + not +done + …I haven’t seen this film.我沒有看過這部電影.She hasn’t finished doing his homework.她還沒有完成她的作業(yè).
一般疑問句：① Have / Has + 主語 + done + … Have you seen this film ? Yes, I have. / No, I haven’t .你看過這部電影嗎?是的, 看過. / 不, 沒有.Has she finished doing his homework ?Yes, she has . / No, she hasn’t.她完成她的作業(yè)了嗎?是的, 完成了. / 不, 沒有.
特殊疑問句：① 特殊疑問詞 + have / has + 主語 + done + …When has you seen this film ?你什么時(shí)候看的這部電影?Who has finished doing his homework ? 誰完成了作業(yè)?
標(biāo)志詞時(shí)間狀語：典型的表時(shí)間的詞與現(xiàn)在完成時(shí)連用
與for 、since、 already、 yet、 ever、 never、 recently、just、before、 so far、 by now、 …等連用.注意: for+一段時(shí)間 since+過去的某一個(gè)時(shí)間點(diǎn)
I have lived in Nanning for ten years.I have lived in Nanning since ten years ago/ 2002.I haven’t eaten anything for ten hours.I ha haven’t eaten anything since 6am.
already :用于肯定句, 可放在助動(dòng)詞之后、過去分詞之前，也可放在句末.I have already finished my homework.
yet: 用在疑問句中意為”已經(jīng)”, 用在否定句中表示”還”, 常放在句末.Have you finished your homework yet?I haven’t finished my homework yet.
ever: 曾經(jīng) 用于疑問句中：Have you ever been to Beijing?Have you ever been to Shanghai ? 你去過上海嗎?
never: 未曾 從未I have never traveled by plane before.我以前從來沒有乘飛機(jī)旅行過.
recently：最近 用于肯定 否定 疑問句中I have been busy recently.We have not seen Tom recently.Have they been here recently.
現(xiàn)在完成時(shí)的23個(gè)“標(biāo)志詞
以下的詞匯，通常使用“現(xiàn)在完成時(shí)”結(jié)構(gòu)。1)ever since, since, since then——3個(gè)2)by now, so far, till/until now, up to now——5個(gè)3)before, lately, recently——3個(gè)4)in recent years;in the past——2個(gè)5)in/for/over/during the last/past +時(shí)間段——2個(gè)6)This/That/It is + 最高級結(jié)構(gòu)… (that) +從句用現(xiàn)完——1個(gè)7)This/That/It is the first/second… time (that) +從句用現(xiàn)完——1個(gè)8)This/That/It is the only…(that) +從句用現(xiàn)完——1個(gè)9)不很常見的up to the present, to date, thus far——3個(gè)10)不很常見的long ago, from——2個(gè)
用法現(xiàn)在完成時(shí)既涉及過去，又聯(lián)系現(xiàn)在
1.現(xiàn)在完成時(shí)不能單獨(dú)與準(zhǔn)確時(shí)間連用，(如表示過去的時(shí)間狀語)如:yesterday(morning、afternoon),last(morning、afternoon)等，除非與for,since連用.
2.現(xiàn)在完成時(shí)往往同表示不確定的過去時(shí)間狀語連用如:already(肯定，句中)，yet(否定，疑問，句中)，just,before,recently,still,lately,never等：He has already obtained a scholarship.他已經(jīng)獲得了一份獎(jiǎng)學(xué)金。I haven’t seen much of him recently (lately).我已經(jīng)很久沒有看到他(最近的)。We have seen that film before.我們以前已經(jīng)看過那部電影了。Have they found the missing child yet?他們找到失蹤的孩子了嗎?
