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小升初必备语法:比较since和for

日期:2013-6-26 15:09 阅读:

 

  Since 用来说明动作起始时间,for用来说明动作延续时间长度。

  I have lived here for more than twenty years.

  I have lived here since I was born..

  My aunt has worked in a clinic since 1949.

  Some new oilfields have been opened up since 1976.

  I have known Xiao Li since she was a little girl.

  My brother has been in the Youth League for two years.

  I have not heard from my uncle for a long time.

  注意:并非有for 作为时间状语的句子都用现在完成时。

  I worked here for more than twenty years.

  (我现在已不在这里工作。)

  I have worked here for many years.

  (现在我仍在这里工作。)

  小窍门: 当现在完成时+一段时间,这一结构中,我们用下面的公式转化,很容易就能排除非延续动词在完成时中的误使。

  1) (对) Tom has studied Russian for three years.

  = Tom began to study Russian three years ago, and is still studying it now.

  2) (错) Harry has got married for six years.

  = Harry began to get married six years ago, and is still getting married now.

  显然,第二句不对,它应改为 Harry got married six years ago. 或 Harry has been married for six years.

Tags:小升,必备,语法,比较,since