u状态动词如state、signify一般不用进行时。
u即便是对于平行结构,如果有明确的时间状语,根据时间状语来选择时态。
u一般将来时钟will可以引导多个平行的将来动作:She will walk to school in the morning and run home in the afternoon.
u有一种微妙的情况:用过去进行时描述背事件,而用一般过去时描述在前段的更重要的事件。(若前后都是一般过去式,则前后两件事情的重要性一样。
1.现在完成时:可以是从过去持续到现在的行为,也可以使一个已经完成的行为但现在仍然有影响。
u标志词:since, within the past … , in the last…
uWhen情况:when 既可以表示at the same time,也可以表示after。但如果when用现在完成时,则表示“after”
u如果动作发生的前后顺序已经交代的很明显,多数不需要用过去完成时。
Antonio drove to the store and bought some ice cream.
l一般由but和and连接的句子不需要使用过去完成时。
lBefore,after连接的句子已经清晰的表明了动作发生的先后顺序,不必用过去完成时。
u也可以用时间而不是一般过去式来表示later past moment:By 1945, the United State had been at war for several years.
u一种狡猾的句型:现实一般过去式,后用过去时间即过去完成时。
The band U2 was just one of many new groups on the rock music scene in the early 1980’s, but less than ten years later, U2 had fully eclipsed its early rivals in the pantheon of popular music.
通常时态的顺序为:一般时+将来时;过去式+conditional
The scientist believes that the machine will be wonderful.
The scientist believed that the machine would be wounderful.
u标志词:if, as if, as though
u虚拟语气中,be一般用were (无论主语是第几人称,都不用was而用were),只是表示虚拟,并不表示过去时间。
(二)If 句式(if…then…,then一般省略)
1.表示确定: If present, then present
EG: if she eats pizza, (then) she becomes ill.
2.表示某种程度的不确定: if present, then can or may
If she eats pizza, (then) she may /can become ill.
3.将来确定:if present/present perfect,then future.(if X happens/has happened, Y will happen.)
If she eats pizza tomorrow, (then) she will become ill.
If Sophie HAS EATEN pizza, then she WILL BECOME ill.
4.将来不太可能发生:if 假设虚拟,then conditional(if X were to happen, Y would happen)
If she ate pizza tomorrow, (then) she would/could become ill. (使用虚拟语气)
5.过去从未发生: if past perfect,then conditional perfect
(If X had happened, Y would/could have happened)
If she had eaten pizza yesterday, (then) she would/could have become ill. (使用虚拟语气)
注意:美式英语中,GMAT中,if 引导的从句中不能出现Should 和would 不能进入if从句中。
1.不定式不加to(动词原形Be , do):没有-s;用be而不用is,are,am
2.句式: 主语+命令性词汇+that+从句主语+动词原形(that不能省略,不允许用should)
We propose that the school board disband.
u只能接that的:demand, dictate, insist, mandate, propose, recommend, request, stipulate规定,讲定, suggest(当没有第二主语是,porpose也可以接不定式 The attorneys proposed to meet the following day.)
u只能接to do的:advise, allow, forbid, persuade, want
u即可以接that又可以接to do:ask, beg, intend, order, prefer, urge, require
u特殊情况:prohibit sth;prohibit from doing;prohibit sb from doing
Right: His demand THAT he BE paid full severance was not met.
uIt’s X句型,如果X是一个形容词,如essential,传达紧急感的,即可以用命令虚拟语气,也可以用不定式。
如:It is essential that Gary be ready before noon.
It is essential for Gary to be ready before noon.
一些传达紧急感的形容词性的命令词汇既可用虚拟语气,也可用不定式:如essential, advisable, crucial,desirable, fitting, imperative, important, mandatory, necessary, preferable, urgent, vital
u当suggest表“可能代表”的意思时,而不是表达“建议”的意思时不能用虚拟语气。
u不要使用除了be 动词以外的动词来构成被动语态;such get
uby+动作的执行者;表示用什么工具或方法用意是用 through 和because of 。
u通常情况下主动语态比被动语态简洁,但不要对被动语态有偏见。不在不得已的情况下,不要用语态做排除选项的关键。
有时候听上去很正确的主动语态也会隐藏着错误,例如:
It has been decided by Jason that he will not attend college next fall.
Jason has decided next fall not to attend college.
时间状语next fall是表示将来的,不能和现在完成时态 has decided挨在一起。
1.normally+eats; is eating+right now; will eat+at tomorrow’s party
2.wear a helmet是本句中事件发生的背景状态,用过去进行时was wearing a helmet;
by+was struck;escaped+in that episode.
3.1971过去时间,不能用现在完成时,改为一般过去式。
用build表示作者可能继续讨论building process;用had built表示作者可能继续讨论destruction。
6.Alread提示该动作是个瞬间动作,用完成时。本句中wake up是在phone rang之前完成,用过去完成时:改为She had already waken up when the phone rang.
7.主句为一般过去式,will have 改为 would have;did not back up改为had not backed up
8.知识点:也可以用时间而不是一般过去式来表示later past moment:By 1945, the United State had been at war for several years.
9.General rules,用一般时,if it is cooled
10.正确。知识点:将来不太可能发生:if 假设虚拟,then conditional(if X were to happen, Y would happen)
11.正确。知识点:将来确定:if present/present perfect,then future.(if X happens/has happened, Y will happen.)
12.Want+不定式,改为 want him to stay;insist+命令虚拟,正确
13.By+was developed;is converted正确。
扩展:如果全句都划线,当作者的意图是进一步讨论fischer-tropsch时,仍应使用被动语态,不应改为主动语态。
14.By Picasso有歧义:如果picasso是修饰painting的改为:The dealer was asked to sell a Picasso painting.如果picasso是动作发起者,改为:Picasso asked the dealer to sell a painting.
15.Have to 与 require重复;require+命令假设改为be tested。
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