现在完成时和现在完成进行时
若我们脱离现所处的三维空间进入四维空间，会发现可以进入过去或未来的任意一段时期。 part 1 现在完成时(have+过去分词)
现在完成时描述的是从过去某时到现在为止这一段时间中发生的状况， 可用于表示“继续”、“经验”、“完成”、“结果”。
1）继续：表示从过去继续到现在的动作或状态，因此往往与和现在有关的表示一段时间的时间状语连用。
e.g. for+一段时间 since+过去某时 all+时间
so far/up till now
in the past/last few years
recently/lately/up to these few～ this week/month/years these days/months/years how long
e.g. He has suffered mightily at the hands of the scholars and the public since 1887 appearance of A Study in Scarlet.
*注意看环境时态，有时时间状语也可用于其它时态
思考题1:
—has your father returned from Africa yet?
—Yes, but he____ here for only three days before his company sent him to Australia. A. was B. has been C. will be D. would be
*since引导的从句中的动词用过去时（从某时起的瞬间动作发生于过去），主句原则上应当用现在完成时，但用“It is+时间…”引导的句子除外。（旁观者视角）（许多老师会说相当于has been，这样不便于理解，但方便记忆）
e.g. It is twenty years since we made our first appointment.
*“When…?”疑问句不可以用现在完成时，因为这是用来询问瞬间动作时间的，而用于表示继续的现在完成时不谈瞬间动作的时间。 e.g. When did you visit Sweden？
2）经验：表示从过去到现在的经验，即从过去到现在之间曾经经历过或做过的事情。因为当事人现在还有印象，所以用现在完成时，且有时可以不用时间状语。
思考题2:
Eliza remembers everything exactly as if it _____yesterday.
A. was happening B. happens C. has happened D. happened
常用时间状语： often/never ever
before
once/twice/…time
3）完成：表示过去开始的动作现在刚刚结束。
e.g. Yet it should be noted that by \engage in the rich man's sport, in 1914, of driving an automobile.
思考题3:
从传统意义上说，收获应该是在秋天，但是科学使收获在几乎每个季节都变得可能。（in the conventional sense)
思考题4:
The price________, but I doubt whether it will remain so.
A. went down B. will go down C. has gone down D. was going down
*already V.S. yet
already在肯定句中表示已经完成
yet在肯定句中表示转折，否定句中表示还未完成，在疑问句中表示已经完成。
4）结果：表示过去动作的结果对现在仍有影响。往往不必用时间状语。 e.g. I know I ought to have spoken to Lord St.Simon, but it was dreadful hard.
思考题5:
这方法不管用，但是，在我看来，一个小的改变可以使它大不相同。（enormous）
思考题6:
I still have by me a little portrait of her, in which I can see her as she then was, looking so young that she might have been __(1)__for the elder sister of her daughters, sitting sideways in an attitude which was habitual to her.
Lucile Bucolin came from a West Indian family: she had either never__(2)__her parents or lost them very early.
That Alissa Buclin was pretty, I was incapable yet of perceiving ;and yet Juliette might have been __(3)__more beautiful, but this beauty of her sister 's grace seemed something external, some-thing which lay open to the whole world at the first glance.
I had hardly seen Abel Vautier this year; he had__(4)__with-out waiting to be called up.We met again with pleasure. I was afraid of finding him changed ;but he had merely __(5)__more confidence without losing any of his charm.
A. enlisted B. taken C. considered D. known E. acquired G. reaching
*运用时间状语时，时态要根据说话时的具体情况而定。 He didn't finish his task this
afternoon.—说话时已经过了下午。
He hasn't finish his task this afternoon.—说话时还是下午。 *运用地点状语有时会限定时态
e.g1.我在巴黎买的这条围巾。 I bought the scarf in Paris.
“在法国”这个地点状语限定了买围巾这个动作发生在过去，所以不能和现在联系，用过去时 2.我买了这条围巾。 I have bought the scarf.
买围巾的动作和现在的情况联系，表示已经买了（现在不用买了等）
现在用不同的时态来表示同一意思 e.g. 他离开中国三年。
一般过去时—He left China three years ago.
一般现在时—It is three years since he left China.
现在完成时He has been away from China for three years.
*just now V.S. just
just now一般用于过去时，而just用于现在完成时
*现在完成时 V.S. 过去完成时
现在完成时表示延续到现在或与现在有关系的动作，而过去完成时表示的是延续到过去某时已经完成的动作。
现在完成时不可以与表示具体过去时间的词连用，而过去完成时可以与其连用，表示过去的过去。
*根据整体语言环境进行综合分析 思考题7:
The discussion ____alive when a heated topic was brought in. A. was coming B. had come C. has come D. came 思考题8:
Look at the timetable.Hurry up! Flight 4026_____off at 18:20. A. takes B. took C. will be taken D. has taken
part 2 现在完成进行时
现在完成进行时描述的是从过去某时开始一直延续到现在，而且会继续进行下去。 现在完成时侧重于动作的结束或完成，而现在完成时则侧重于动作的未来结束和继续进行。 1.强调动作还未结束，会继续进行
2.强调动作延续时间的长久或带有感情色彩
有些动词如live，learn，snow等用于现在完成时并不表示动作已完成，所以既可用于现在完成时，也可用于现在完成进行时。
e.g. I've been waiting for my carry-out for three hours！
3.表示在现在阶段之前反复发生
e.g. He has always been thinking of July but he can't see her.
*有些动词不能用于现在完成进行时
表示状态的动词：be，have，exist，belong等 表示感情的动词：like，love，hate，detest等 表示感觉的动词：see，hear，feel，sound 等
其它：believe，doubt，wish，agree，include，order，known
*现在完成进行时不与never，ever，yet，already等连用（即现完与其表达含义矛盾）
思考题9 :
In glancing over the somewhat incoherent series of Memoirs with which I have endeavored to__(1)__a few of the mental peculiarities of my friend Mr.Sherlock Holmes, I have been struck by the difficulty which I __(2)__in picking out examples which shall in every way answer my purpose.For in those cases in which Holmes has performed some tour de force of analytical reasoning, and has demonstrated the value of his peculiar methods of investigation, the facts themselves have been so__(3)__ that I could not feel __(4)__in laying them before the public. (1) A. question B. write C. illustrate D. recall (2) A. have experienced B. have been experiencing C. experienced D. had experienced
(3) A. horrible B. commonplace C. convincing D. unique (4) A. convinced B. surprised C. justified D. satisfied
*本次思考题答案：
1. A 父亲已回来，但又在公司送他去澳大利亚前走了，与现在无关，故选A。易误选B。 2. D 记忆是现在的，事情就像昨天发生。故选D。易误选C。
3.In the international sense, harvest should be in autumn, but science has made it possible in almost every season.
3. C 价格降低的动作现在刚刚结束。
4. The method has not worked, but, in my view, one small change can make an enormous difference. 5. B D C A E
7. D 提出话题与讨论活跃是同一时刻发生 8. A 时刻表客观不受时间推进的影响
9.（1） C. illustrate “浏览不知怎么支离破碎的系列回忆录和我之前所努力尝试的”是为了解释我的朋友与众不同的思维，否则就应用endeavored。
（2） A. have experienced 在挑选例证过程中我被困难所打击，动作持续到现在但没有表示会继续进行。
（3） B. commonplace 根据前文由于Holmes表示出他分析推理的绝技，（而）事实本身总是那么平凡。（所以我被困难打击）
（4） C. justified 由前方逻辑线可推出因此我在把它们展现于公众眼前时感到不合理。