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现在完成时的“完成”用法和“未完成”用法 (1)现在完成时的“完成”用法 现在完成时的“完成”指的是动作发生在过去某时刻并已结束，但该动作对现在有影响，与现在情况具有因果关系。在这种用法中，动作是非延续性的，因此只能与表示不具体的过去时间状语 (already, yet, just, before, recently等)、频度时间状语(never, ever, once等)、包括现在时刻在内的时间状语 (this morning, today等)连用。 He has seen the film. 他已看过这部电影。(动作结束于过去，但说明的是现在情况：他了解该电影的情节。) She has opened the window. 她已把窗子打开。(动作发生在过去，但说明的是现在的情况：现在的窗子开着。) Jane has just cleaned the room and it is very clean now.简刚打扫完房间，它现在还很干净。 人教高中英语单词mp3 人教版初中英语mp3 人教版高中英语电子课本 (2)现在完成时的“未完成”用法 现在完成时的“未完成”用法指的是动作开始于过去的某个时间，持续到现在，也许还会持续下去，常与下列表示包括现在时间在内的时间状语连用，如for ..., since, lately, recently, in/during/over the past/last/recent/few/two/three ... years/weeks/months ..., up to now, so far, to date等。 It has rained every day so far this month.这个月到目前为止每天都在下雨。 He has studied English for 5 years.他学习英语五年了。 She left school three years ago and has worked as a nurse ever since. 她三年前毕业，从那时起便一直当护士。 注意：come, arrive, leave 等终止性动词的现在完成时在肯定句中不能与表示一段时间的状语连用。 若表达终止性动词动作发生了多长时间，常用下列表达法： ①状态动词 be ＋表语＋for 时间 ②It is/has been＋一段时间＋since 从句 She has been back for a week.＝It is/has been a week since she came back.她已回来一周了。 The school ________ I visited the other day was not the one ________ I once studied. A. that; which B. which; where C. where; which D. where; where 【答案】B 【解析】句意：我前几天参观的学校不是我曾经学习过的那所学校。第一个定语从句缺少visited的宾语，用that/which引导定语从句；而第二个定语从句则缺地点状语，用where引导，故B项正确。 Wind power is an ancient source of energy ________ we may return in the near future. A. on which B. by which C. to which D. from which 【答案】C 【解析】考查“介词＋which”引导的定语从句的用法。句意：风能是一种古老的能源，我们在不久的将来可能会重新利用它。return to sth.“回归到……”。 Generally speaking, the media can often help solve problems and draw attention to the cases________ help is needed. A. where B. when C. which D. whose 【答案】A 【解析】句意：一般来说，媒体通常能帮助解决问题并且将人们的注意力吸引到需要帮助的地方。定语从句中若先行词为case, situation, point, condition, stage等词时，通常使用where来引导。 We went through a period________ communication was very difficult in the rural areas. A. which B. whose C. in which D. with which 【答案】C 【解析】a period作先行词，且在定语从句中作时间状语。介词in通常和period搭配，in...period意为“在……期间”。故选C。 During those years the four young men gave many concerts ________ they played all their latest songs. A. at which B. for which C. for whom D. at whom 【答案】A 【解析】句意：在那些年，这四个年轻人举办了许多演唱会，在演唱会上他们演唱了他们所有的最新歌曲。分析句式结构可知，此处考查“介词＋关系代词”引导的定语从句，根据at the concerts“在音乐会上”可知，A项正确。 
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