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上�？釋W酷玩夏令營講解英語語法：since和for的區(qū)別

上�？釋W酷玩夏令營介紹，since 用來說明動作起始時間，for用來說明動作延續(xù)時間長度。

since和for的區(qū)別：

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 作為時間狀語的句子都用現(xiàn)在完成時。

i worked here for more than twenty years.

(我現(xiàn)在已不在這里工作。)

i have worked here for many years.

(現(xiàn)在我仍在這里工作。)

上海新東方夏令營提示，小竅門：　當現(xiàn)在完成時+一段時間，這一結(jié)構(gòu)中，我們用下面的公式轉(zhuǎn)化，很容易就能排除非延續(xù)動詞在完成時中的誤使。

1)　(對) tom has studied russian for three years.

= tom began to study russian three years ago, and is still studying it now.

2)　(錯) harry has got married for six years.

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

顯然，第二句不對，它應改為 harry got married six years ago.　或 harry has been married for six years.