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to do 与 doing的区别

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It's time 后接不定式 todo 或 接不定式doing,之间有何区别? Eg:it's a waste of time ________ in such a long queue.横线上添 1. waiting,2.to wait之间的区别。
解题思路: to do 与 doing的区别
解题过程:
如果用it's time that....的结构的话,后面的从句中要使用一般过去式如:it's time that we went to school 到了我们去上学的时候了
如果用it's the second time that.... 中间的序数词可以使用其他任意的序数词。在这种句型中,后面的从句要用完成时,如果前面的it's中的s是is 后面用现在完成时,如果是was则要用过去完成时。
it's a waste of time waiting in such a long queue 后面用动名词,这是it作为形式主语后面动名词作为真正的主语使用的结构。
附动名词和不定式作主语和宾语的语法给你参考。
一,作主语
⒈不定式作主语
动词不定式作主语时,句子的谓语动词常用单数,其位置有以下两种:
(1)把不定式置于句首.如:
To get there by bike will take us half an hour.
(2)用it作形式主语,把真正的主语不定式置于句后,常用于下列句式中.如:
①It+be+名词+to do
It's our duty to take good care of the old.
②It takes sb + some time +to do
How long did it take you to finish the work
③It+be+形容词+for sb +to do
It is difficult for us to finish writing the composition in a quarter of an hour.
④It+be+形容词+of sb +to do
It is stupid of you to write down everything the teacher says.
⑤It seems(appears)+形容词+to do
It seemed impossible to save money.
在句型③中,常用表示客观情况的形容词,如:difficult, easy, hard, important, impossible, necessary 等;在句型④中,常用careless, clever, good, foolish, honest, kind, lazy, nice, right, silly, stupid, wise等 表示赞扬或批评的词.在不定式前的sb,可看作其逻辑主语.这一句式有时相当于Sb is+形容词+to do句式 ,如:It's kind of you to help me with my English.=You are kind to help me with my English.
⒉动名词作主语
Learning without practice is no good.
动名词作主语时,也常用It句式.如:
①It's +no good(no use, fun, a pleasurea waste of time)+doing…
It's no good reading in dim light.
It's no use sitting here waiting.
②It's+形容词+doing
It's dangerous swimming in the sea in windy days.
这样用的形容词有expensive, nice, tiring等,但important, necessary则不适用于这种结构,应用不定式 代替,如:It's important for you to keep fit.
③There is no + doing
There is no saying what will happen next.
在这一结构中,动名词后常带宾语,相当于"It's impossible to…"结构.
⒊动词不定式和动名词作主语的区别
①不定式作主语经常表示具体动作,常与特定的动作执行者联系在一起;而动名词作主语经常表示抽象动 作,经常不与特定的动作执行者联系在一起.如:
It's no good eating too much fat.
It's no good for you to eat so much fat.
②动名词结构作主语,可以用名词或代词属格形式作逻辑主语.如:
It's no use your pretending that you didn't know the rules.
二,作宾语
⒈不定式作宾语
①以下动词后,只能跟不定式作宾语.如:agree, ask, aim, arrange, choose, decide, demand, expect, fail , help, hope, lean, long, manage, offer, plan, prepare, pretend, promise, refuse, wish等,这些词大部分可接that引导的从句.如:
I decided to ask for my money back.
I decided that I would ask for my money back
最终答案:略